Our next presenter is Duncan Craib, Managing Director and CEO of Boss Energy. He's the Managing Director and CEO of Boss Energy, having joined in 2017. Chartered accountant, extensive mining sector experience. He's had senior roles across Australia, the U.K., Namibia, and China, with a focus on uranium since 2007. Before joining Boss, Mr. Craib was Finance Director at Swakop Uranium, where he was instrumental in the AUD 2.5 billion acquisition and AUD 2.8 billion development of the Bahu Submine in Namibia. His expertise spans finance, mine development, uranium trading, and corporate governance. Thanks, Dun.
Thanks, Andrew. Thanks to the commitment and hard work of our team, we've just beaten our first year of production and cost guidance, and then a few weeks ago hit over GBP 1 million of uranium production in that first year. Honeymoon's margins are strong, our balance sheet is robust, and we are well positioned to capitalize on the inevitable upturn of the uranium market, which we believe as demand rises on the back of the nuclear power resurgence. With production on track to ramp up significantly during this current year, we see the financial strengths of Honeymoon come to the fore and cash flow set to increase substantially. In parallel with the ongoing ramp-up, we are driving our exploration program forward with the aim of creating new and establishing new resources.
This will see an updated resource estimate for our satellite deposits, Goldstem and Jason, in the coming quarter, and also work to be done on progressing greenfield targets. Before I get into the detail, it's worth keeping in mind what an amazing opportunity Australia has to pursue uranium mining. Despite Australia's tremendous potential, there are only three operating uranium mines in Australia: BHP's Olympic Dam, Heathgate's Four Mile operation, and in the past year, Boss Energy's Honeymoon uranium mine. Honeymoon became South Australia's third operating uranium mine, and for that matter, Australia's newest uranium producer in the past decade, one of the first to re-enter the global market and with that take first mover advantage. With its political and economic stability, Australia has a once-in-a-generation opportunity to contribute in achieving net zero and capitalize on the inevitable surge of global uranium demand that will accompany it.
Australia's untapped uranium resource opportunity is immense. About 1.7 million tonnes is estimated in our country, with extensive reserves in Northern Territory, Queensland, Western Australia, and South Australia. In fact, Australia holds one third of the world's uranium reserves, but as a producer, we only supply 7% of the global uranium demand. To put that into context, we as a country with only three mines operating in South Australia export enough uranium to provide 67% of Australia's national electricity market with zero carbon emission nuclear power. Think about it. What an amazing opportunity we have that we're not capitalizing on. On a world scale, recent industry events reflect what could be a positive turning point demonstrated by several positive catalysts. The uranium market has seen renewed strength since April, recently driven by rising government support, expanding nuclear programs, and resurgent financial interest.
Globally, demand is rising as nuclear energy programs gain policy momentum. China began construction on six new reactors. India is accelerating approvals for 21 units, and Japan extended reactor lifespans above 60 years following what the U.S.A. is doing with their expanding fleet. As Chris highlighted this morning, SMRs are also gaining traction, with Canada investing in early deployment. The term price indicators could be more reactive positively in the coming months. There's Boss Energy, and this is why we entered production, why we started up last year. Over the past decade, Boss Energy has evolved from a small startup into becoming an international multi-mine in situ recovery or ISR producer in the two Tier 1 locations of South Australia and South Texas. As mentioned, we've just produced our one millionth drum of pounds of uranium. We've banked nearly AUD 100 million in our first year of operation.
Our ramp-up is going to plan with 1.6 million pounds estimated for production this current year. Our interest in Alta Mesa is managed by enCore Energy. We have a 30% interest in which we get 30% of their produced uranium. Already, they've delivered 100,000 pounds to Boss Energy, which is unencumbered, and we can sell into our own sales mix. That 30% joint venture investment into enCore Energy's managed Alta Mesa mine in South Texas was our first foray into mergers and acquisitions. We're truly focused on value creative opportunities as we look to take advantage of getting a foothold into the U.S.A. uranium industry, which helps power 17% of that global superpower's energy needs.
We look forward to continue working closely with the enCore Energy team and helping ramp up Alta Mesa, which is really growing strength to strength quarter by quarter, with recent management changes and a recent new direction seeing benefits flow through. As a company, our key focus remains on seeing Honeymoon go through successfully its ramp-up and increase its production profile. In addition to that, and in addition to our Alta Mesa investment, we've also looked at increasing and growing our pipeline of other opportunities within the global uranium industry. That is principally highlighted by Boss Energy recently increasing our investment into Laramide Resources up to 19.9%. It is wonderful to get a foothold on that asset, Westmoreland in Queensland, which has just received a mineral development license, which is a hugely positive milestone as we firmly believe Queensland will inevitably open up to uranium mining.
In addition to that, as mentioned, we're focusing on our satellite deposits in South Australia, Goldstem and Jason, looking to bring those into production. We're also drilling around the uranium mine with Lake Constance and other exciting sort of greenfield exploration targets. In the Northern Territory, we've got an earn-in arrangement with Eclipse Mining for their Liverpool project, and that project itself was held by Cameco back in 2004 to 2006. Laramide is not just Westmoreland, it's also got projects in Utah, in South Texas, and further afield in Kazakhstan. There are wonderful growth opportunities to look forward to. Let's get to the main part, which brings me to Honeymoon. What a journey it's been. These uranium mines take a long time to develop, and it's something the market often missed.
For Honeymoon itself, it's taken nearly 50 years to get from the initial drilling discoveries in the 1970s to get to commercial production of where we are today. In the 1970s, it started drilling, and there you can see Dave Brunt in his red trousers and flares at the bottom with a backyard swimming pool testing out ion exchange and how that works. Dave's still with us, consulting, but really this just shows what the trajectory has been for this project. It took time, but we got there, and it now is a commercial success. When we look at the development times, milestones that we've achieved over the past decades, there have been a number of them as we've advanced this project. In December 2015, having acquired the Honeymoon mine, January 2020, it was followed by our first feasibility study.
In the following year, in June 2021, we did an enhanced feasibility study introducing ion exchange as our main method of production, which really enabled us to increase our production output and lower our costs of actual operations. In June 2022, we then made the final investment decision. This was followed by April, two years ago, in April 2024, we restarted production, and in January of this year, we declared our commercial production, and with that provided our first guidance. By April this year, we were generating free cash flow positive, and only a month ago, or in June, Honeymoon exceeded that first-year production guidance of GBP 850,000. As highlighted, Honeymoon exceeded that FY 2025 production and cost guidance with 873,000 uranium produced and second half C1 cash costs of AUD 23 per pound.
Our operating NIM6 columns are performing in line with design, and our initial wellfields one to three are all operating at flow capacity. We're operating at main capacity. Here we can see the columns being constructed. These are columns four to six going from left to right. Column four has just done its hydro testing, getting ready to be brought online. Columns five and six are now practically being completed, getting ready for their hydro testing so that they can be brought into production. Their commissioning is likely to take place over these coming quarters of this current calendar year. When we look at our wellfields, we're also expanding, and here you can see the outline, the square box of our mining license, within which sits the ore body, which is really broken down into three domains.
On the left, you can see Goldstem, the center, the Honeymoon domain, and then the East Kalkaroo. The Honeymoon domain is where the processing plant sits and those wellfields sitting adjacent to where we started production. We're now looking further afield and bringing in our sort of satellite deposits from wellfield 6 to 9. Our C1, last week we released our FY 2026 guidance, which represented our second year of Honeymoon's ramp-up. Production guidance is GBP 1.6 million, which is consistent with what was set out in the 2021 feasibility study. Our C1 cash cost is AUD 41 to AUD 45 per pound, which represents a AUD 4 per pound increase on those C1 costs, which is primarily attributed to an expected decline in grade as we move into these outer areas of the resource.
This was understood in our feasibility study, and our team on site are pursuing several initiatives to optimize the lixiviant to leach the uranium and deliver value through improved recoveries. Sustaining capital expenditure for the years is forecast to be AUD 29 to AUD 32 million, which reflects the capital to build four to five wellfields and bring the total number of wellfields in operation to nine, which is required to deliver our current year FY 2026 production guidance of that GBP 1.6 million. In addition, it supports another GBP 900,000 for the following FY 2027 year, which we will expand upon. As it's noted in our quarterly announcement, results from the initial drilling for wellfields six to nine have shown less continuity of mineralization as was assumed in the feasibility study, which potentially means that we have additional injection and extraction wells required, which results in an increase in sustaining capital expenditure per pound.
As a company, our primary focus is to now assess the potential challenges this poses and what optimizational techniques we can apply to ensure Honeymoon's positive start to production continues for years to come. In a combined approach, we have harnessed our own skilled team on the ground with external subject matter experts to proactively work on such matters. I can't shed any more light on that now because that's why we're doing the review, but we'll keep the market informed as the results come to hand and tackle these challenges as we have to get to this point after the past 10 years. In parallel to the Honeymoon mine ramping up, we are also proactively exploring and proving up those satellite deposits of Goldstem and Jason. Jason sits about 15 km north of our Honeymoon mine, and Goldstem sits about 80 km northwest of the Honeymoon mine.
We have the potential to drive growth as well as enable us to leverage off our existing infrastructure and further capitalize on the opportunity presented by that growing global demand for uranium in Tier 1 locations. As mentioned, the results of our mineral resource estimate upgrade for these satellite deposits will be provided to the market in the coming quarter. At the end of this quarter, I'll be handing over the reins of CEO to Matt Dusci, who I've had the pleasure of working closely with over the past year. His significant technical capability and vast operating experience will be invaluable as Boss Energy continues to ramp up production. I look very, very much forward to working and supporting with Matt in my new role as Non-Executive Director of the company and supporting our board, which has also recently been bolstered by the appointment of two highly experienced directors, Ms.
Joanne Palmer and Ms. Carolyn Keats. It really has been an honor steering Boss Energy on the path from project development to production, working with so many skilled and talented Australians and supportive stakeholders and shareholders in collectively making Honeymoon Australia's only new operating uranium mine in Australia in the past 10 years. Thank you.