I would now like to hand the conference to your speaker today, Adam Hinckley. Please go ahead, sir.
Good afternoon, and thank you for joining us on today's conference call to discuss Enphase Energy's Q4 2020 results. On today's call are Badri Kothandaraman, Enphase's President and Chief Executive Officer, Eric Branderiz, Chief Financial Officer, and Raghu Belur, Chief Products Officer. After the market closed today, Enphase issued a press release announcing the results for its Q4 ended December 31st, 2020. During this conference call, Enphase management will make forward-looking statements including, but not limited to, statements related to Enphase Energy's expected future financial performance, the capability of our technology and products, our operations, including in the manufacturing and customer service, the anticipated growth in our sales and in the markets in which we operate and target, the performance of the tools we make available to and the capabilities of our installation partners, and expected regulatory changes.
These forward-looking statements involve significant risks and uncertainties, and Enphase Energy's actual results and the timing of events could differ materially from these expectations. For a more complete discussion of the risks and uncertainties, please see the company's annual report on Form 10-K for the year ended December 31st, 2019, which is on file with the SEC, and annual report on Form 10-K for the year ended December 31st, 2020, which will be filed with the SEC in the Q1 of 2021. Enphase Energy cautions you not to place any undue reliance on forward-looking statements and undertakes no duty or obligation to update any forward-looking statements as a result of new information, future events, or changes in its expectations. Also, please note that financial measures used on this call are expressed on a non-GAAP basis, unless otherwise noted, and have been adjusted to exclude certain charges.
The company has provided a reconciliation of these non-GAAP financial measures to GAAP financial measures in its earnings release posted today, which can also be found in the investor relations section of its website. I'd like to introduce Badri Kothandaraman, President and Chief Executive Officer of Enphase Energy. Badri.
Good afternoon, thanks for joining us today to discuss our Q4 2020 financial results. We had a good quarter. We reported a revenue of $264.8 million, shipped approximately 2.3 million microinverters, achieved non-GAAP gross margin of 40.2%, and generated strong free cash flow of $78.5 million. We exited the Q4 at approximately 40%/13%/27%. This means 40% gross margin, 13% operating expense, and 27% operating income, all as a percentage of revenue on a non-GAAP basis. As a reminder, our baseline financial model is 35%/15%/20%. Eric will go into greater details about our finances later in the call. Let's now discuss how we are servicing customers. Our customer experience personnel in all four worldwide locations, the U.S., Europe, India, and Australia, are still working from home while supporting installers and homeowners.
Our Q4 net promoter score worldwide was 62%, compared to 67% in Q3, and our North America net promoter score was 68%, compared to 71% in Q3. Our average call wait time increased in Q4 to more than five minutes as we onboarded new installers and fielded more calls relating to our storage systems. We are not happy about this increase in wait times and are working to bring them back to under a minute. The ramp of our Enphase storage system has also increased call volumes as our installers are learning how to commission the system and homeowners are learning about the system's features. Let's now talk about manufacturing. Our operations team did a great job flexing manufacturing as 2020 played out.
When the pandemic began, we cut manufacturing in Q2 of 2020 and then had to quickly ramp back up to meet the surge in demand in Q3 and Q4. The production in Q4 was more than two times the level in Q2. I'm very pleased with the ramp of our Mexico factory that met our target of producing more than 1 million units in Q4. As part of our supply chain strategy to diversify production to tariff-free and cost-competitive locations globally, we began microinverter production at Salcomp, India in October of 2020 and started shipping to customers during Q4. We have a high-quality, state-of-the-art automated line with a quarterly production capacity of half a million units and the space to add a second line with the same capacity. The production ramp is going very well, and we expect to produce approximately 400,000 microinverters in India in Q1.
We have seen a strong increase in demand for our microinverter systems over the past several months as we continue to onboard new installers. The uptick in broad economic activity has stressed the global semiconductor supply chain. We are seeing constraints on a few semiconductor components used in our microinverters. Our existing suppliers are working very hard to increase the availability of components for us, which, coupled along with the new suppliers we are qualifying, should help easing the constraints into the Q2 of 2021. To put the supply constraints into perspective, we see this as a more manageable situation than the high voltage AC FET shortage we experienced in late 2018, early 2019. In terms of our battery pack supply, our second supplier began delivering cell packs in Q4 as planned and will be ramping capacity throughout the H1 of 2021.
We expect to have 120 MWh available to us in the Q3 of 2021. We have adequate supply of cell packs with two suppliers, although we are continuing discussions with additional suppliers for geographic diversification. Let's now move on to the regions. Our US and international revenue mix for Q4 was 82% and 18%, respectively. We saw sequential revenue growth in all regions during the quarter and record sell-through from distributors to installers. The US market was quite strong in Q4. U.S. revenue was up 55% sequentially. The sell-through of microinverters from our distributors to installers increased nearly 40% from Q3, which was also a record. As a result, the channel inventory for microinverters at the end of Q4 remained slightly lower than our target range of 8- 10 weeks.
We expect channel inventory to remain at these low levels through the end of Q1 due to strong demand and the semiconductor supply constraints. We continued ramping shipments of our storage systems nicely. We shipped 35% more MWh in Q4 compared to Q3. In Europe, we reported record revenue for Q4. Revenue increased 10% sequentially. On an annual basis, the revenue from Europe increased 32% in 2020. Annualizing the Q4 revenue from Europe would have put us close to achieving our pre-pandemic target of doubling the revenue in the region. I am very pleased with our team's performance, and I'm excited about the region's projected growth in 2021 as the new markets we recently entered continue to gain traction. We will also be introducing our Enphase storage system for the European market later in the Q3 of 2021, adding yet another growth driver.
In Australia, we built on our strong Q3 results and achieved record quarterly sell-through and record installer count in Q4. The results were fueled by the launch of our Enphase Installer Network, or EIN, as well as growing demand for our high-power IQ7A microinverters, plus a favorable competitive environment as regulations continued to shift towards safer and smarter solar. We expect to introduce our Enphase storage system for the Australian market during the Q4 of 2021. In Latin America, we reported record quarterly revenue. Puerto Rico showed strength for our microinverter systems as well as our storage systems. Now that we have covered the regions, let's discuss overall bookings for Q1. Our customer demand for Q1 significantly exceeds the high end of our guidance range for Q1. We are constrained by the semiconductor component availability, as we discussed earlier.
Our top priority is to take care of our installers, and our teams are working hard to minimize customer disruption. We have already factored in expedited costs into our Q1 guidance to ensure we put maximum number of units in customer hands. Let's cover our storage roll-up. We shipped 32 MWh of storage systems in Q4, representing a growth of approximately 35% compared to Q3. Around 360 unique installers had commissioned at least one Enphase storage system by the end of Q4. We are learning tremendously from the installers and homeowners and are thankful to them for enduring with our earlier mistakes and errors. We have made many updates to our software as well as our release process as a result of their feedback.
Overall, we are very pleased with the market interest in our storage system, although we did fall a little bit short of our internal shipment expectations for Q4. I attribute this to growing pains and ramping a new product as we actively work with installers on selling, installing, and commissioning this new product category that is much more complex and time-consuming than solar-only systems. With the strength of the microinverter system demand being so good, the long-tail installers naturally default into prioritizing solar-only systems that they know how to service best. Enphase has a responsibility to therefore ensure a best-in-class installer experience and ease of doing business for both solar plus storage installs. In addition to the long-tail installers, we are working with a number of large installers. We recently announced storage agreements with Sunnova, Solar Optimum, and Momentum Solar.
These announcements provide confidence in a continued steady ramp in shipment volumes into 2021. We expect storage shipments to grow nicely in Q1 at a similar rate as Q4, despite the negative seasonality of the industry, in each Q1. Coming back once again to long-tail installers, they are our top priority, and we have made major modifications to our commissioning process to reduce installation and commissioning times for storage to sub 24 hours. This helps crew scheduling be more predictable and helps the installers' profit on storage installs. With the installers facing labor constraints, the improved commissioning times should help incentivize them to sell solar plus storage than just focusing on solar only. Let's talk about more new products that we are coming out with. We recently announced that our storage systems are now compatible with existing M215 and M250-based solar systems.
The expanded compatibility provides approximately 300,000 additional Enphase system owners in the U.S. with the possibility of achieving energy resilience through the Enphase Upgrade Program. We are also working on additional features to our Enphase storage system to make it a lot more powerful. These include generator compatibility, load control, power control, and 200% overload. We expect to release these features shortly. Let me cover them quickly one by one. Homeowners can add generators to their Enphase system. With our system, a generator ATS, an automatic transfer switch, is not necessary, thereby driving down cost and simplifying the install. Homeowners can configure the generator's behavior from their Enphase app. The system can turn the generator on when the grid fails, either immediately or when the battery charge is below a certain level. Next is load control.
With this new feature, a homeowner will be able to control up to four critical loads by connecting them up to the Enphase system. The homeowner can reconfigure the behavior of the system via the Enphase app. He or she can identify non-critical loads, such as pool pump, to automatically turn off when the grid fails or based on the state of charge of the battery. This ensures that the home does not black out during a grid outage, thereby providing a good customer experience. The next feature is called PCS, Power Control System. It's a software capability in our system to regulate its output in a manner which does not increase the amount of current on the homeowner's main load center. This avoids an expensive upgrade of the main load center when a homeowner wants to add both solar and storage.
The last feature, and an important one, is the 200% overload. Motor loads such as ACs and well pumps have a significant power need during startup, which if not met, will black out a home. One way to solve the problem is to throw more dollars at it, which is to oversize a storage system, which is expensive. We solve this problem with an intelligent hardware and software-based function called Power Start. In addition, we have increased the capability in our microinverters to supply up to 200% of the rated power for short duration in order to start motors, ensuring that the home does not black out. An Enphase storage system with this feature will help the homeowner optimize his system size and maximize value. Next, we are making progress on our IQ8 grid-independent solar microinverter.
We already have IQ8 alpha systems with and without Enphase storage running at various sites. We expect to complete beta installations and expect to begin shipping production in Q2. Our small commercial solution, based on IQ8D 640-W AC microinverter, is making similar progress. Similar to residential solution, we expect to provide a complete solution that includes the microinverter system and a comprehensive digital platform to capture the entire journey of the installer and the system owner. The platform will provide a sophisticated design and proposal tool, permit package development service, commissioning, activation software, tools for operations and maintenance, performance tracking, and fleet management. We have begun alpha installations here and expect to start shipping production in Q2. Let me next talk about our portable power station, previously referred to as Ensemble in a Box. We are a little bit behind here, but have a good plan going forward.
This will be our first consumer product. It will provide energy security indoors as well as energy on the go when you go outdoors. It is cloud connected and controlled via the Enphase app. We view this as a starter product for homeowners who are not yet ready to invest in a full solar or storage system. The product will support up to 1.3 kWh of storage, provide 1.6 kW continuous, and 3.2 kW of peak power. It will keep the home's basic appliances such as lights, mobile devices, refrigerators on for a few hours during an outage. We expect to release this product during the Q4 of 2021. Let's now cover digital transformation. I'm excited about our two recent acquisition announcements. The first one is Sofdesk. Headquartered in Montreal, Sofdesk provides design and proposal software for use by solar and roofing companies.
The second announcement is the proposed acquisition of the solar design services business of DIN Engineering. Based in Noida, India, the business provides rapid and cost-effective proposal drawings and permit plan FETs to installers. We expect to close this acquisition by the end of Q1. These two acquisitions will add significant capabilities to our digital platform. By providing such tools and services to the installers, we aim to simplify the sales process while reducing soft costs and providing an enhanced buying experience for homeowners. Turning to the other aspects of our digital platform, we have now onboarded 440 installers in North America to our Enphase Installer Network, or EIN, through a highly selective process focused on installation quality and homeowner experience. We launched our EIN in Australia during Q4 and look forward to launching EINs in Europe and India next.
Our EIN installers can enjoy a variety of tools and services on Enphase's digital platform to make the sales and installation process faster and easier. We have modified our highly interactive Enphase system estimators tool to enable accurate sizing of storage systems with various home appliances. Installers can leverage this tool to provide an improved homeowner experience. We recently announced that Allison Johnson has joined Enphase as our CMO, Chief Marketing Officer. Her experience at some of the world's leading brands is key as we look to accelerate our growth and establish Enphase as a recognized consumer product leader in the global transition to home electrification and full energy independence. We are happy with our performance. We are excited about the strength in worldwide demand, the ramp of our storage systems, our upcoming new products, and our digital transformation efforts.
With that, I will hand the call over to Eric for his review of our finances. Eric?
Thanks, Badri. Good afternoon, everyone. I will provide more details related to our Q4 of 2020 financial results, as well as our business outlook for the Q1 of 2021. We have provided reconciliation of these non-GAAP to GAAP financial measures in our earnings release posted today, which can also be found in the IR section of our website. We are very pleased with the significant increase in demand for our microinverter systems in Q4 2020, despite the pandemic. Total revenue for Q4 2020 was $264.8 million, which did not include any revenue from safe harbor shipments during the quarter. Total revenue increased 48% sequentially, and we shipped approximately 762 MW DC of microinverters and 32 MWh of storage systems in Q4 2020. The 32 MWh is equivalent to 12.2 MWh of power.
As we previously discussed, some of our microinverter units met certain size and weight criteria, qualifying them for an exclusion to the Section 301 tariffs on prior shipments. We requested refunds totaling approximately $39 million plus accrued interest, of which $23 million were approved in Q3 2020 and $16 million were approved in Q4 2020. These refunds have been accounted for as a reduction of cost of goods sold in the respective quarters where they were approved and the associated accrued interest was recorded in other expenses. We have excluded past tariffs refunds from non-GAAP financial results to present a more accurate picture of ongoing business performance. We don't expect any further refunds in 2021. Non-GAAP gross margin for Q4 2020, which excluded the $16 million tariff approved refund, was 40.2% compared to 41% for Q3 2020.
The sequential decline was due to higher shipping and logistics costs related to component supply constraints. GAAP gross margin was 46% for Q4 2020. Non-GAAP operating expenses were $34.2 million for Q4 2020 compared to $29.6 million for Q3 2020. The sequential increase was primarily due to the hiring of 85 employees during the quarter, mainly focused on engineering, customer experience, and innovation. GAAP operating expenses were $42.8 million for Q4 2020 compared to $43.2 million for Q3 2020. GAAP operating expenses for Q4 2020 including $7.8 million of stock-based compensation expenses and $684,000 of acquisition-related expenses and amortization for acquired intangible assets. On a non-GAAP basis, income from operations was $72.4 million for Q4 2020 compared to $43.7 million for Q3 2020. On a GAAP basis, income from operations was $79.1 million for Q4 2020 compared to $51.8 million for Q3 2020.
On a non-GAAP basis, net income for Q4 2020 was $71.3 million compared to $41.8 million for Q3 2020. This resulted in diluted earnings per share of $0.51 for Q4 2020 compared to $0.30 per share for Q3 2020. On an annual basis, we are pleased to report a record non-GAAP net income of $188.5 million. GAAP net income for Q4 2020 was $73 million compared to GAAP net income of $39.4 million for Q3 2020. GAAP diluted earnings per share was $0.50 for Q4 2020 compared to diluted earnings per share of $0.28 in Q3 2020. Now turning to the balance sheet and the working capital front, inventory was $41.8 million at the end of Q4 2020 compared to $37.5 million at the end of Q3 2020.
The sequential increase in inventory was driven by the planned increase of raw materials for our Enphase storage systems in anticipation of the production ramp in 2021. Although the dollar value of inventory increased sequentially, days of inventory of ton decreased to 27 days compared to 41 days in Q3. This sequential decrease in days of inventory was driven by the higher shipment volumes in Q4. Our target is 30 days nominally, and we will always do what is right for customers. Accounts receivables were $182.2 million at the end of Q4 2020 compared to $122.4 million at the end of Q3 2020. The sequential increase was due to the higher revenue in Q4. DSO of 50 days decreased slightly from 52 days in prior quarter due to our collection management. We remain committed to efficient working capital management and driving down our cash conversion cycle.
We exited Q4 2020 with a total cash balance of $679.4 million compared to $661.8 million for Q3 2020. We did not make any share repurchases against our $200 million share repurchase authorization. We spent $16.3 million on withhold-to-cover tax transactions on employee stock vesting that prevented the issuance of approximately 132,000 shares in Q4. For the calendar year 2020, we spent $68.3 million at an average price of $50 per share on withhold-to-cover transactions and prevented the issuance of approximately 1.4 million shares. In Q4, we also spent $43.9 million on the partial repurchase of convertible notes due 2024. Since the end of Q4, we have received additional conversion requests of $61.5 million as the notes are deep in-the-money compared to the conversion price. We expect to repay the principal amount of this conversion request in cash and in-the-money amount in shares. Settlement will occur in Q1 2021.
In Q4 2020, we generated $84.2 million in cash flow from operations and $78.5 million in free cash flow. For calendar year 2020, we generated a record $188.9 million of free cash flow. Capital expenditure was $8.9 million for Q4, mainly for the Enphase storage manufacturing capacity increase, IT enhancements, Enlighten software app development costs, and the production ramp with our second contract manufacturing partner. Capital expenditure for 2020 was $20.6 million. Let's discuss our outlook for the Q1 of 2021. We expect our revenue for the quarter to be within a range of $280 million-$300 million. We expect GAAP gross margin to be within a range of 37%-40% and non-GAAP gross margin to be within a range of 38%-41%, which excludes stock-based compensation expenses.
The gross margin guidance includes a further increase in shipping and logistic costs to ensure we are best servicing our customers and getting them as many units as possible. We expect our GAAP operating expenses to be within a range of $64 million-$67 million, including a total of approximately $22 million estimated for stock-based compensation expenses and acquisition-related expenses and amortization. We expect non-GAAP operating expenses to be within a range of $42 million-$45 million. All guidance estimates include the Sofdesk acquisition but do not include the DIN Solar design services business. I would like to touch upon our OpEx guidance. Our non-GAAP operating expenses are increasing quite a bit from Q4 to Q1. The increase is due to two reasons. Hire to support our growth plans and consolidation of acquisitions, plus related incentive accruals.
The hiring is related to the new product development and investment in innovation to create best-in-class home energy management systems. The Sofdesk and DIN Solar design services business acquisition are building blocks that enable us to build a world-class digital platform for homeowners and installers. At the same time, we are not taking our eyes off the baseline financial model and plan to maintain operating expenses at 15% of revenue. Before turning the call back to the operator for questions, I would like to mention a couple of things. First, we published our inaugural ESG report a few weeks ago. Sustainability is at the core of what we do at Enphase, and we are proud of our team as we continue to enable clean energy and energy independence through innovation. Second, Enphase has been recently added to the S&P 500 Index, and we are very proud of this accomplishment.
I want to acknowledge the hard work and dedication of the entire Enphase team. With that, I will now open the line for questions.
Thank you. As a reminder, to ask a question, you will need to press star one on your telephone. To withdraw your question, press the pound key. Please stand by while we compile the Q&A roster. Our first question comes from Brian Lee with Goldman Sachs. Your line is now open.
Hey, guys. Thanks for taking the questions, and congrats on a great quarter. Maybe first, if we could sort of dig into the guidance a little bit. I know there's some shortages here on the micro side. I'm assuming there's some on the battery side as well, but can you give us a sense of sort of supply-demand for both the micro side as well as the Encharge system? It sounds like you're leaving some business on the table here. Can you kind of quantify what impact that's having on Q1, and is that expected to also persist to Q2? Related to that, I guess on gross margins, what % hit did you see? Is it 100 basis points? Is it more than that on Q4, given the additional freight and logistics costs you had to incur?
Yeah. Let me start with the microinverters. Demand is quite high. Customer demand is quite high there, and I once again go back and attribute it to our high quality and high customer experience. Basically, while I'm not going to quantify how much the demand is higher compared to the high end of the guidance, I already said it is significantly high. Our constraints basically are coming from the semiconductor components. That's an industry-wide issue right now. There are two specific components that we are constrained on. One is our ASIC that goes into the micro, and the other is the AC FET drivers that actually drive the high voltage FET. There, the name of the game is we are qualifying multiple more sources so that we have more supply as well as expediting product.
I am in direct touch with the CEOs of those companies, and they are helping as much as they can. We expect to get all caught up basically by early April. Our top priority through all of this is to ensure that we take care of customers. We will do whatever it takes in order to ensure their lines are running and that they are not affected. That's on the microinverter side. On the storage side, we have enough capacity. We already said that as of last quarter, we had about 50 MWh of capacity, and then as of Q3 of 2021, we will have 120 MWh of capacity. We have enough capacity on the storage side. On the storage side, once again, reflecting back on how we did, we started shipping storage in the Q3. I'm pretty happy with the ramp.
Compared to the Q3, we did about 35% more MWh in Q4 compared to Q3. For Q1, we do expect to do a similar amount higher than Q4. Let me come to some more statistics on storage so that you get a flavor for it. Essentially, like what I said, about 360-plus unique installation companies have installed at least one Enphase storage system. We have trained over 650 unique installation companies. We have trained overall more than 1,200 installation personnel. What we are seeing, we have learned a lot in the process, mainly from installers as well as a lot of homeowners, and we are improving them one by one. Although, I said in the prepared remarks, I wish we had shipped a little bit more, I think we are doing the right things by fixing these problems.
For example, our commissioning time needs work, and we are in the process of improving the commissioning time to sub 24 hours. For us, it is all about taking care of the installer, making sure that the installer's experience is seamless. Ease of doing business is what we are all about. Therefore, we will never compromise on the short-term in order to achieve that. More examples is, very often, the installers usually struggle on storage with main panel rewiring and replacement. That's a big pain point for the installers, and we are working on steps to solve that. When it comes to other ease of doing business, the homeowners are still in their infancy on learning how to use storage systems.
While the transition from on-grid to off-grid is seamless, the fact it is seamless means that the homeowners do not change their behavior, and Enphase needs to do a lot more there to educate the homeowner in a seamless way. This is intelligent notification, intelligent text messaging, intelligent load control, which we are actually working on. One more thing is to also go back and do the storage design right in the first place. Very often, people miss that storage is all about taking care of power properly. Most of the people miss that. Once again, it is we, Enphase, needs to take responsibility to do whatever it takes to simplify the installer's ease of doing business. Of course, now I'm coming to the industry changes that are needed. Permitting needs to be a little bit faster on storage.
That's an industry-wide problem, which I'm sure many of our peers and us are going to be working on. The last one is financing for storage. We need some kind of innovative financing schemes on storage so that that also starts accelerating overall. I hope I gave you some flavor. If I were to summarize, we are growing at a very nice clip, 35% in Q4 compared to Q3. We'll do similar rate in Q1 compared to Q4, and our focus is on the long term. We will take care of our installers, training, and making our storage system easiest install. That's our focus.
Thanks, Badri. That's super helpful color. Maybe just, I had a second question on batteries. You touched upon some of this, but if I kind of back into the numbers, it seems like you did maybe $25 million-$30 million of Encharge revenue in Q4, and that'll be well into the $30 million+ range in Q1, based on the guidance. First question on batteries is, fair to assume those are the right revenue ranges and there's no change to pricing in the near term? Second question is just on, I know given it's a new product, and the installation rates are not as sort of swift as what you're used to on the solar side. Your shipments are not keeping up necessarily with capacity. You've talked about 120 MWh by Q2, kind of 35% surge capacity you want to have in place.
Maybe 85, 90 MWh really being the shippable capacity you're targeting. When do you think we get closer to shipments lining up with your applicable capacity? Thanks, guys.
Your ballpark for the revenue is right. The second one is like what I said, it's a long-term game. Once we fix the ease of doing business for the installers, we expect to ramp. As you see, we are making significant progress with both the long-tail installers as well as the Tier 1 and 2 installers. You saw all of the press releases. You will see a lot more going forward. We'll continue to grow at a nice clip. You can do the math. If we continue to grow at this 30%, soon we will need a third supplier. That might happen in 2022, and we are already talking to those people.
All right. Thanks, guys. I'll pass it on.
Thank you. Our next question comes from Moses Sutton with Barclays. Your line is now open.
Thanks for taking our questions. Congrats on the quarter. You say you'll start shipping IQ8 in 2Q. How should we think about IQ8 standalone pricing versus IQ7? What might be the range on the premium? Might you expect over time a majority of installers shifting more toward IQ8 versus IQ7, or is the jury out on that question still?
We're not going to talk about the exact pricing right now, but we are within a few months of going to market. That will happen very soon. With regarding whether people are going to adopt IQ8 over IQ7, we think the answer is a no-brainer. It's going to be yes. IQ8 is a grid-independent microinverter system. Therefore, I expect the adoption to be high when it is released. There are obviously a lot of combinations with IQ8, and in some cases, people might prefer to buy IQ8 with a smaller storage system, and we will be promoting the heck out of it.
Great. Looking forward. What percent of U.S. installers using your product now still need to be trained on Encharge? I know you gave the number of installers trained already or having deployed the system. How much is left in the U.S. training process?
Look, we work with 2,000 installers in the U.S., usually. We reported numbers of 650 unique installation companies. That number, we are catching up on those numbers very fast. We expect within a couple of quarters to basically train everyone that matters.
Got it. Just one more from me, and I'll jump back in the queue. What's the annualized contribution from these two recent bolt-on M&As that you know, maybe on revenue and even gross profit, if possible?
We're not going to break out those numbers right now.
Got it. Understood. Thank you.
Thank you. Our next question comes from Mark Strouse with J.P. Morgan. Your line is now open.
Yeah, good evening. Thank you very much for taking our question. Quite a bit has changed in the macro environment since your Q3 call. Can you just talk about how your customer conversations have changed, if at all, since the ITC was extended? Then kind of a follow-up to that is, who knows what's going to happen going forward, but if energy storage standalone is included in some kind of future revision to the ITC, what do you think that impact would be for Enphase, specifically looking for retrofit activity? Thanks.
Yeah. Hi, this is Raghu. Clearly, change in administration is something that's very positive for us. Obviously, the first thing that happened was the ITC extension. As a result, you see all our numbers.
Have no safe harbor in them. That was probably a very significant change that took place. With regards to some bills that are in Congress that are being worked on right now, the one that is really interesting is the one around standalone storage. The nice thing about our architecture, the fact that we are AC-coupled, means that it lends itself very well to a standalone system. The combination of a standalone storage device plus a safety device, the Microgrid Interconnect, can now add substantial value to the homeowner, both in terms of providing resiliency in the event of an outage, plus as well as participating in value-added services such as grid services, for example.
One could even extend their thinking into our portable power station could also someday participate in that as well, in terms of providing both resiliency as well as participating in value-added services. We really are excited about the storage standalone discussions that are going on right now.
In terms of the ITC, I think that the idea that the ITC could be extended into a storage, potentially even a cash refund, that is very appealing, right? Think about it, homeowners, they look at payments, and Badri mentioned financing. All of those things help to create adoption, and as cost keeps reducing and the cost per kWh and cost per W keeps on going down, that ramp can be accelerated, right? We welcome those things.
Okay. Thank you. Just a follow-up to Moses' question on Sofdesk in particular. Is the idea with that acquisition, financially anyway, to create a stickier relationship with your customers? Is there a financial rationale for these acquisitions as well in that kind of standalone, they would meet your corporate target margin profile?
Yeah. You got it right. We love our long-tail installers. We want to make it easy to do business for them. We'd like them to stay on our platform, buy our product, buy our software, buy our permitting services, and a lot more that's coming.
Okay. No problem.
In terms of financially, we look at those transactions, and they stand on their own feet. Rest assured that is there.
Got it. Thank you.
Thank you. Our next question comes from Aric Li with Bank of America. Your line is now open.
Hey, guys. Aric Li with Bank of America. Just a quick question on storage. Given the supply constraints across the industry.
Eric, you got a really bad connection there.
Can you hear me better now?
We cannot hear you well.
Can you hear me better now?
Yeah. Let's give it a try.
Is that better?
Slightly better.
Okay. Just on storage, given the supply constraints across the industry right now, can you talk about your ongoing supplier discussions there? Is there any color you can provide around amount of storage capacity you would expect to expand to near term with your third supplier beyond the two existing suppliers? A follow-up question after that.
Okay. Yeah. Right now we have two qualified suppliers. The first one, we have already ramped well with. The second one is in the process of ramping. They started shipping to us in the Q4. We said that, basically in Q4, meaning the quarter that just passed, we had a supply of 50 MWh . In Q3 of 2021, we expect that supply between these two suppliers to go up to 120 MWh . If we find that we are short, maybe by the time we get into 2022, we are already talking to a third supplier, or rather multiple suppliers, and then it takes us usually anywhere from six to 12 months to qualify the product. We are starting those discussions right now.
Got it. Just to clarify, would you still expect to bring on a third supplier this year, or are you saying that that's more going to contribute into 2022?
We will have a third supplier ready if we need it. Yes, we are starting those activities. That's correct.
Okay. Thank you. Just on the R&D cycle, are there any updates you can provide on the development of IQ9, where that currently stands at this time? Is it still being developed, or is it in testing phase? If you can provide any color there. Thank you.
Yeah. We are actually working on IQ 9 at this time. IQ 9, our vision is basically, obviously smaller, cheaper, faster. Producing a lot more power than IQ 8.
Right now, we are focused on a few areas. One is we'd like to see how to reduce the footprint of the transformers, the e-caps, the 600 volt AC FET devices through some semiconductor process innovation. GaN transistors are becoming widespread. GaN on GaN and GaN on silicon, they are becoming widespread. The advantage that GaN gives is I can now run my AC FETs at a higher frequency. I can run it at a higher frequency, I can reduce my transformer sizes. I can reduce my transformer sizes, the entire footprint can get a lot smaller. Of course, this is me speaking theoretically, and we need to demonstrate that with both prototype vehicles as well as qualifying reliability, et cetera. I expect that to take the next 12-18 months.
We will also be working on the next generation as well to think about maybe sophisticated cooling schemes, alternatives to potting, et cetera, alternatives to meaning. Today we have, between our gate drivers and our AC FETs and our DC FETs, we have a lot of components there. Using semiconductor packaging and GaN, I may be able to collapse all of those to substantially less number of components. We will be looking at those as well. A lot of R&D is going on. We hired our CTO a year ago. His name is Hans. He is an outstanding guy. We have started all of those discussions, and there is a team actually behind it. Whenever Eric Branderiz, our CFO, says innovation, he means that investment in the CTO team. We are investing a lot more than before.
Got it. One last question, I'll pass it on here. Could you just talk about any data points you can give us on traction or progress with the long-tail installers in Europe? How is that training process going?
Long-tail installers, actually, Europe is a great story. If you remember in the 2019 Analyst Day, I had reported that we only had five salespeople at that time in Europe. Now we have, I would say, increased, maybe quadrupled or even more, the number of sales folks. We have a great team there. That team is ramping in Netherlands, in Belgium, in France. We have recently opened up offices in Poland, Spain. We have sales and FAE teams there. We've also launched massive effort in Germany, where we are in the process of training a lot of installers and getting more and more installers on board there. We will also introduce our storage solution into Europe in the Q3. You know, Germany is a big market. It's one gigawatt of PV with 80% attach rate because of the feed-in tariffs being so small.
We're very excited about that market. Having said that, it's a matured market, almost. There are a bunch of suppliers, and we have clear differentiation. It'll take us a little bit of time. With our relentless focus on quality, customer experience, supporting the long tail of installers, I'm sure we'll start making significant progress in that region.
Thank you.
Thank you. Our next question comes from Colin Rusch with Oppenheimer. Your line is now open.
Thanks so much, guys. Can you give us a sense of the progress that you're making in pre-selling the IQ8D, and activity you've got going in the commercial market right now?
Clearly, as we talked about IQ8D brings a lot of value into the commercial segment. Just to remind everybody, the IQ8D, two things. One, the inverter itself has 50% higher power density, and it connects two panels into one device. The second thing is, we are not looking at this as a standalone device itself. We are looking at it as a complete end-to-end solution, and we want to leverage our digital platform. Everything from the design and proposal services that come with it, along with permitting package, a very sophisticated O&M system, fleet management, performance tracking, et cetera. We're looking at bringing a complete solution set to the market. We are in alpha right now. We have alpha installs happening. The installation process is much simpler. We are doing small commercial with IQ7s as well, but it's a significant improvement from IQ7 to the IQ8D.
A lot of progress there. More to come. We'll report more as we make progress.
Great. Just in terms of thinking about the integration of generators with the storage and solar, as you guys look at the competitive landscape, can you speak to the differentiation for the grid formation functionality that you have, and how long you think it'll take before anyone else has a similar sort of capability out in the marketplace?
Yeah, the generator is your question, right? I think the generator integration is a little unique to us. For instance, we have the Microgrid Interconnect Device or Smart Switch. Because of that, we don't need an automatic transfer switch, which is what you typically require with a generator integration. That function is effectively done in software for us. Just by simply the act of connecting the generator into that device, the entire system is now managed by that device and managed by the energy management system. There are a few other advantages as a result of the way we integrate everything into the AC domain, is that the generator can now run in parallel to the storage system.
What that means is the homeowner can configure up their system, and the system will automatically make decisions such as, for example, turn on when the grid fails instantly, turn the generator on instantly as soon as the grid fails. For example, once the grid fails, you only turn the generator on when the state of charge is at a certain level, and then it turns back off when the state of charge has reached another level. Another functionality there is, for example, a quiet period, right? You can configure it up, all done in software. You can configure it all up saying, "Hey, during this time of the night, don't start the generator," so you can reduce noise pollution. It's a very rich experience. You can get to see exactly how the power flow is in real time on your app.
much more well-integrated, one-stop shop solution with integrating generator into a common platform.
All right. Thanks so much, guys.
Thank you.
Thank you. Our next question comes from Philip Shen with ROTH Capital Partners. Your line is now open.
Hi, everyone. Congrats on the strong results. My first question is on when you think you might add the second line in India. Given how low channel inventory is and the overwhelming demand, have you already made the decision to ramp up the second line? If not, why not? What else do you need to see?
We've already made the decision to add a second line. To remind everybody, we have half a million microinverters capacity. We are going to invest in adding another line, which is another half a million microinverters. That will take about six months to come on board. In the meantime, we have interim sources. We have China, we have a lot of capacity there in our Fuyong plant. We have Guad. Guad just reached 1 million microinverters, we are going to be investing in Guad as well in order for us to create a lot more capacity. What we see is, with IQ8 going to come very soon, in one to two quarters, we do see the necessity to increase our capacity. We are going to be working on it.
Okay. Thanks, Badri. When do you expect the second line in India to come online, maybe fully? By the end of the year, if you add up all the capacity, China, Mexico, India, what is the quarterly run rate you think we're at maybe in Q4?
Well, on the India-specific question, I would say six months. On a number for your overall capacity by the end of the year, this is not about demand. This is about purely capacity. I would say between 4 million and 5 million units per quarter is what we'll be prepared for.
Okay, great. As it relates to international, I think on the last quarter you talked about by the end of this year, getting to 70/30 U.S. international mix, would be reasonable and you'd be perhaps even disappointed if you weren't there. What's your latest view on that mix? What do you think it ends up being by the end of the year?
We threw a curve ball in it by shipping the storage systems, which are entirely U.S. We have to ship the international storage systems. In addition to ramping on the solar systems, we'll be doing exactly that. 70/30 maybe by the end of this year may be tough, but definitely middle of next year, I see it as a possibility.
Okay, great. Thanks, Badri. I'll pass it on.
Thank you. Our next question comes from Eric Stine with Craig-Hallum. Your line is now open.
Hi, everyone. Maybe just on, given the really strong free cash flow, I mean your cash balance will soon be pushing $1 billion. Just on capital allocation, are there any areas on the acquisition front, I know you've made a few, seem like they're more strategic on the small side. Any acquisitions or areas in your business it might make sense from that perspective? Is this more about just sticking with product development and organic growth?
I mean, both are gonna be critical, as the challenge with organic growth is that we also generate cash that way, right? Because our framework that we have. The acquisition approach is gonna be very active. We have a lot of things that we need to complement our digital platform. Actually, Raghu and Adam, both of them are working around the clock with our pipeline very healthy, the pipeline of the M&A acquisitions, battery also has its own set of rules in which we need to find the right candidates or targets. That's going to be a very active area. You should see more throughout the year.
Got it. Okay. Any details on, maybe not, but any details on areas that you think, I guess you mentioned the digital platform, but I'm wondering, I think whether it's new geographies or just thinking about potential paths you may take?
Yeah. I think, internally we have a very clear view on what our long-term strategy is for how we're going to continue growing our business. We've talked about this in the past, where we think about every home as being a microgrid, and then interconnecting microgrids and forming pools of microgrids and transacting energy across them. We talk about the significant electrification of homes that are going to happen, which will further increase the demand, electrification between all the appliances getting electrified, EV, et cetera. While we can't provide you specifics, we have, as Eric mentioned, a healthy pipeline of areas that we are looking at, but that should give you some context about how we are thinking about our M&A plan. It's both the digital transformation piece as well as product in order to meet what we have in our strategic plan.
There are no confines on companies within the space, right? We are thinking now is expanding that into other sectors, software and other areas. It's a very diversified pipeline from multiple sources, right?
It's international as well.
It's international.
As we say, the two acquisitions we have done, neither of those are actually in the U.S. at this time. We are looking across the world.
The other one is the ability of the company to absorb and integrate those acquisitions is going to be very important. I feel very confident on Jeff McNeil's organization, in the finance organization. We are used to deal with acquisitions, integrations. It will be a very active place in 2021.
Yep. No, that's very helpful. Maybe just last one from me. Just thoughts on updating the target operating model. I'm trying to think how many quarters it took for you to go from 30/20/10 to the new 35/15/20. You're now at the 40/15/25. Any thoughts on how long you'd like to see that sustained before you officially update that?
Yeah. We want to make sure that we conservatively provide a baseline, and that's what we did with the existing framework. When you're launching new products and you're entering new markets, a lot of things happen. When you're planning on the long term, that's the right framework, right? In the short term, the midpoint of the guidance of the current quarter that we are guiding is the responsible thing in the mid, short term. For the long term, I think that framework is cash-generating. Remember, we got an OpEx, CapEx, and other costs light business model in the company, right? We don't have manufacturing plants. Our CapEx is going to be higher this year, but at the same time, we can continue operating with the contract manufacturing approach.
This framework should stay like that until you can probably get an update when we do our next state, if there is an update.
Okay. Thank you.
Thank you. Our next question comes from Jim Ricchiuti with Needham & Company. Your line is now open.
Hi. Thank you. Good afternoon. I know it's early days for storage, I'm just wondering, given what you're seeing in terms of demand trends and the competitive landscape, and I guess the potentially more supportive government policy initiatives, I'm just wondering, is this changing your view of how pricing might be trending in the market looking out over the next year or so?
I think our view is, when it comes to things like particularly around pricing, et cetera, and the trend, our view is we have to continually add value, right? What that means is that it's not just thinking about storage as a widget or a storage as a battery, right? It has to be an integral part of a complete solution, an energy management solution that includes solar, that includes storage. How does the whole thing, entire system integrate load management, generator integration? You've seen the announcement where we are working with a fuel cell company, et cetera. For us, it's not about a specific widget and a specific widget's pricing. That's really not how we think about it. We think about it in terms of how can we do the complete solution and add value for our installer partners and the homeowner.
Okay. Fair enough. Should we anticipate any change as we think about the mix with respect to storage, long-tail installers, and your tier 1, tier 2 installers over the next one year or so?
No. I think what we have today is right.
Okay. Thanks very much.
Thank you.
Thank you. Our next question comes from Maheep Mandloi with Credit Suisse. Your line is now open.
Hi. Thanks for taking the questions. Badri, maybe this question is for you on the storage product. You did say that there are some delays in installation. It's taking time to train the installers. That seems to be more applicable to also your other competitors. I just wanted to understand if you're seeing that for other products launched by your competitors in the market as well, or is that something specific to Encharge solution, which is impacting those delays?
I'm not going to comment on the other competitors, but we take pride in supporting our long-tail installers. Many of them may not even have done storage once. They have a lot of demand, as you can expect. Our job is to train them, so that they can start doing storage installs seamlessly. Right now, we introduced this product in July. As of the end of December, 360+ long-tail installers, unique installation companies, have installed one Enphase storage system. That's a major win for us. We continue to add 10-15 installers every week there. We have trained over 650+ unique installation companies again. That's also a win. I'm sure we can amp our game up there, because there are thousands of installers, and I'm sure we can do a better job there, which we will be focused on.
In terms of the people, assuming every installer has got at least two people to train, we have trained roughly over 1,200 folks. I would say, we do things. We have a unique business model. We focus on the long tail. Our job is to make that installation smooth and seamless. That's what we will do. It's a long-term game. We're not going to take our eye off the ball there.
Got you. Thanks for the explanation. Just on the new acquisitions and the digital strategy, could you maybe talk about what's the goal here in terms of reducing that soft cost? I think a couple of the solar developers have talked about $7,000, $8,000 per customer of soft costs. Is the idea here to kind of bring it down similar to probably what the soft cost is in Europe and Australia? What's your thinking process here? I have just a quick follow-up after that as well. Thanks.
Yeah. Soft cost is an outcome of what our goal is. Our goal is to provide our installer partners with the best service possible. Installer partners actually as well as the homeowners. We have mapped out a very detailed journey of both how the entire installation process as well for both the installers as well as our homeowners, starting with leads all the way through design, proposal, permitting, procurement, commissioning, installation commissioning, permission to operate, O&M, et cetera. If we do an amazing job on that and where we create a very powerful platform, and these acquisitions that we're talking about are important elements of that journey, then I think the natural outcome of that is going to be a reduction in the soft cost.
We are starting with a very clear focus that this is about bringing great value for our long-tail installer partners.
Maheep, this has been a focus of the industry for quite a long time, and everybody gravitates back into the easiest part of the value chain, which is reduce the cost of the panel, reduce the cost of the hardware, things that are easy or tangible. When you're thinking about, for example, simplifying and streamlining permitting, you're talking about multiple counties, multiple different approaches, different timing, different locations. It's a much more complex problem to tackle. That's the problem that we are tackling. As Raghu said it, we are tackling by understanding the problem from the installer point of view and solving that individual problem. That incorporates pretty much every aspect of lead gen all the way through commissioning and post that, the O&M process, right? Which we are digitizing in many fronts, right? These acquisitions basically fill those gaps.
Got it. No, that's helpful. Just last one, just housekeeping. The megawatt shipped in the quarter, does that include microinverters shipped to the storage product as well, or is that just for the solar shipments?
We will have to get back to you on that. I think right now my off-the-cuff answer is it basically only includes the microinverters that are pure solar, and it does not include the microinverters inside the batteries. We will have to get back to you on that.
All right. Thanks for taking questions.
Thank you. Our next question comes from Joseph Osha with JMP Securities.
Hi there. Thanks for taking my question. I've got two completely unrelated questions. The first relates to DERMS management as regard your storage business. You kind of alluded to this a little bit, Badri. We've seen Enbala get sold, AMS get sold, Stem go out. Might we see you make an investment in sort of the software infrastructure to really offer a fully integrated DERMS capability to your customers or to utilities?
Obviously we won't talk specifics, but, in general, here's our view. Clearly, we see that it's a value-added service anytime with every single storage system that you sell. Given that, and given that we already have a pretty powerful platform, I think, our first step is ensure that at least that we have partnerships that we can fit into existing platforms that are out there. There are a number of people who are out there. We fit into those platforms. There are a number of programs, whether that's in the East Coast or even here in California, that we can participate in those programs as we continue our ramp on storage. I think for us, it's a pretty natural extension on how to incorporate what's called coordination of these DERs and management of these coordinated DERs onto our platform.
I think that's a pretty natural extension for us.
Okay. That's interesting. You would not have a problem, say, making sure that you operate well with AutoGrid or somebody like that.
Absolutely. If there are existing programs, we would do it. Yes.
Okay
communications, et cetera, is getting standardized anyway.
The second completely unrelated question. It's interesting hearing you talk about wide bandgap FETs. Can we imagine a world where all of the high energy MOSFETs in your device are GaN, or I was kind of surprised you didn't mention silicon carbide. Is that the way this is headed?
No, I did not mention silicon carbide. I think we think GaN is the way to go. Obviously we are only scratching the surface. We are working with a few companies. GaN on GaN and GaN on silicon are two interesting technologies. They will help us reduce our footprint, support high power, I mean, everything that we want.
I get just over time, and I assume that obviously at the moment you're probably silicon over time, we can reasonably expect to see those individual little high power sockets probably go wide bandgap over the next couple of years. Is that the idea?
Yeah.
All right. Thank you so much.
Thank you. Our next question comes from Sameer Joshi with H.C. Wainwright. Your line is now open.
Thanks for taking my questions. Just a couple, digging into the storage. In terms of sort of bottlenecks or headwinds, do you see it more from, like a slow draining of installations, installers, or is it because the customers are not educated enough or maybe pricing is not right? The corollary question is, do you find the Encharge 3 versus Encharge 10 demand different? Do you see any change in sizing of the products going forward?
No, like what I told earlier, maybe when I answered Brian Lee's question, I went through the details. Let me cover them once again. Basically, there are several things that can go wrong for the installers on storage. There are some things that we are squarely responsible for Enphase. Like the installers want to come onto a job site, and they want to finish their install, and they want to leave within 12 hours. If our commissioning time is excessive, we are going to place burden on installers. We understand that. We are working with them to rapidly reduce that commissioning time. That's an example. The second one is very often installers have to come in and rewire the main panel, and that is often several thousands of dollars.
If we can help them create a solution which does not need that's ease of doing business for the installers. That's number two. Number three, as homeowners start to experience these storage systems, they are going to be calling installers often. For example, when you switch from on-grid to off-grid, if you haven't made any adjustments in your lifestyle and your grid is out, your external grid is out, utility grid is out, then you're going to quickly run out of storage in three or four hours because your air conditioner is going to be on. Therefore, people who do not even know that they are off-grid run out of storage, and they're out of power, and they call installers, and the installers have to go and help them. It's another truck roll for them. That means lost profit for them. How can Enphase help there?
In order to eliminate all of those problems for installers, make it so easy that an Enphase system seamlessly provides intelligent notification for homeowners. How can an Enphase system seamlessly provide load control?
The homeowner can automatically set in the app saying, "When I switch to off-grid, do not turn off my AC." You maximize your storage system's life. Right? Going back to it all is, even when the storage system is being designed in the first place, as a consultative sale between the homeowner and the installer, what can Enphase do is to make sure that complete transparency to the homeowner, so that it's simple, yet complete.
I think those are things that are entirely in Enphase's control, and it would be remiss if we don't take responsibility there. That's one. I talked about the industry, overall industry. Overall industry, there are problems with permitting cycle times are too long. It's not acceptable. Our peers all need to fight that battle. The last one is, just as financing for solar is getting a lot more mature, financing for storage needs to attain that maturity. What happens is more people will They're comfortable with monthly payments than a lot of cash up front. Those two are industry problems that we'll be working on. It's a combo of Enphase specific stuff, which we are going to put a lot of energy on, and industry changes that we are going to try to influence.
Those are the things we need to do in order to ensure we start ramping much more than our already nice ramp run now.
Understood.
Sameer.
Thanks for that. Yeah.
Many of the comments made by Badri are not unique to Enphase. We are approaching this, we are training installers that they never done an installation before, storage. They are doing really well with microinverters. For them to say, "I need to incorporate on my sell pitch a new product," convince the homeowner that it's a great product. When they do that, after that, get everything lined up with the crews, with the commissioning, and do the installation, complete the training and everything. It takes time, right? Right now they are basically hand to mouth with the microinverter systems, right? We decided to launch with the long tail. That's an investment that we are making.
Once they've made the investment using our system, we believe they will have a hard time switching to a potential alternative because they are all trained, they know our technology, they know our pitch. With that, concurrently, we have interest from Tier 2s and Tier 1s that they are sophisticated. They've done installs before. They've kind of completed that process with competitive products, and they feel our product, it will be an easy train, right? All of those things are being attacked at the same time.
Yeah, no, it is certainly commendable actually that you have identified the exact problems that you are facing, sort of the teething troubles, and are actively addressing those. That is encouraging. Just switching gears a little bit. You mentioned that in your Q1 outlook, the DIN revenues are not included. I thought that DIN was some sort of a back office kind of a support for improving your operation performance as against a revenue-generating source. Am I looking at it wrong?
Yes, you're not right. DIN basically provides permitting services to installers for revenue.
In addition to permitting services, they also provide design and proposal services. The whole point is how can installers get the right paperwork, the permit plan sets, in 24 hours. Once again, it is for us, the fit is obvious because that's what we care about. Anything that our long-tail installers care about, we care about even more.
Right. Last one. Over the last several years, you have had several instances of these supply constraints. Now that you're sitting on approximately $700 million, is there any effort towards going upstream?
No. We're very clear. We're going to be CapEx light, OpEx light. In this case, this was because we never expected such a massive increase in demand coming out of the pandemic. Maybe we should have, but we didn't. Obviously it's because our product is well-received. It's a high quality. I've always told you the target is 500 DPPM and great customer experience. Those are our mantras. We didn't anticipate such a big increase, we are somewhat constrained because of that. Having said that, it's not as severe as what we had in the past. We are looking at adjustments in the way we run the company going forward on how to not allow a situation like this to happen. That's what we do. We learn from our mistakes, and we are going to put in the right business processes.
There's no need to change our approach. It's a capital light approach.
Understood. Thanks for taking my question.
Thank you. Our next question comes from Biju Perincheril with Susquehanna. Your line is now open.
Thank you. Thanks for taking my question. Obviously, very early in the rollout of the storage product, from the initial demand trends that you're seeing, any thoughts on what level of attachment rates we can see looking out a few years? Three or five years out?
We refrained talking about attach rates. We actually gave you megawatt hours, which is a lot better than attach rates. You can calculate the attach rate. It's a complex function of the states you are in. Like for example, the storage may be more popular in California than in some other state. The metrics are different, so we cannot just talk about attach rate without any context, which is why we gave you megawatt hours. I would not like to talk about attach rates. I'd like to talk about megawatt hours. Like what we talked about, we are growing at a steady clip, Q3 to Q4, 35%. Q4 to Q1, expect a similar rate. That's the progress we are making on megawatt hours.
On megawatt hours, is there a number that we can sort of target looking out a few years or you're not ready to give line involvement time guidance?
It's hard for us. Right now, this product is in early stages of ramp. It's hard for us to give a number right now. It'll take us a few more quarters.
That's fair. Thanks.
Thank you. I am not showing any further questions at this time. I would now like to turn the call back over to Badri Kothandaraman for closing remarks.
Thank you for joining us today and for your continued support of Enphase. We look forward to speaking with you again the next quarter. Thank you.
Ladies and gentlemen, this concludes today's conference call. Thank you for participating. You may now disconnect.