Hello, everybody. I'm Paul Scott. I'm the Chief Executive of Renew Holdings, and I'm here today with Sean Wyndham-Quin, our Chief Financial Officer. In terms of format of the presentation, what we're going to cover, I will start with a quick overview of our results, provide a quick overview of our business model, and a reminder of our key differentiators. Sean's going to provide a run through the financials. There's a slide that reflects the performance of recent acquisitions, as well as our ongoing acquisition criteria. We'll provide an overview of our five market sectors, and we've summarized the progress that we're making on our ESG journey. To conclude, I will amplify the strengths of our investment case and provide an outlook.
So turning to slide 2 of the deck, we are delighted to be presenting yet another set of record results for the group that have once again exceeded market expectation. They include strong cash generation and deliver continued earnings growth. We, like most, are feeling the headwinds of the macroeconomic and geopolitical events, but as these results have further demonstrated, our model and our strategy is extremely resilient. It should be remembered that in this period, at the turn of last year, the country was facing a fight with the Omicron infection, a significant event and should be remembered in the context of these strong results. I remain immensely proud of my colleagues and the entire workforce of Renew, who are facing these challenges head-on.
We're also delighted to announce the acquisition of Enisca, a water engineering expert, and more of this developed shortly when I talk to the environmental segment within our results. Our order book remains strong, yet conservatively reported and reflecting the confidence in our progress and our prospects, we have increased the final dividend to GBP 0.1133, representing a full year dividend of GBP 0.17. At the bottom right-hand side of this slide, you'll see we've listed our now 11 independently branded subsidiaries. On to slide three, well, you'll see that we've illustrated some representative images of the sectors we operate across, directly delivering a wide range of multidisciplinary services.
Our markets continue to be described across the five sectors of rail, of infrastructure, which includes our telecommunications, highways, and aviation activities, of energy, environmental, and our specialist building activity remains focused on high quality residential, science, and landmark in London and the Southeast. On slide four, we amplify our differentiators. These are the key ingredients to our ongoing success and our resilience. Our chosen markets have regulated long-term committed funding characteristics. The Autumn Statement included a commitment to protecting capital budgets with an emphasis on the role of infrastructure in rebuilding and growing back the economy. Maintenance and renewal services remain non-discretionary, critical on the networks where we operate. Our OpEx-focused activities have a much lower risk profile and inherent inflation protection.
The vast majority of our contractual terms are actual cost recovery based via frameworks, and task sizes are relatively, small, with longevity of execution relatively short, again, providing protection, against, inflationary factors. Our direct resources are deployed in some very complex and challenging environments that have naturally high barriers to new entrants. Now, compounding earnings growth is demonstrable proof of the resilience in our model, even under the acute challenges that I've just mentioned. And finally, we remain both responsive and innovative, constantly seeking out improvements in value and delivery effectiveness.
Thanks, Paul. Jumping straight to slide six, we've set out our usual chart here, where we set out our financial highlights over the last five years. Pleased to say that all the charts continue to move in the right direction. The one obvious anomaly that jumps out there is the dividend in 2020, where we didn't pay an interim dividend that year as a consequence of the first COVID lockdown. But other than that, all the metrics moving in the right direction, particularly the one we're really focused on, which is the adjusted EPS. Moving on to the income statement. Delighted to say the revenue has increased by 7% to GBP 849 million, and we've seen a 15% increase in our operating profit to GBP 58.8 million.
This increase in operating profit has been part driven by the improvement in our operating margin to 6.9%, up from 6.5% in the previous year, and that's really driven by the mix of work that we're working on, the mix of projects that we've got, and the maturity of the control cycle. So when we're in the peak point of the rail control cycle, we're able to deliver more operational efficiencies, which drive margin improvements. Also pleased to say that our EPS has increased by 18% in the year to GBP 0.595, although I would add that this is at 19% corporation tax rate.
While I would expect to see continued improvement in our profit after tax over the next coming years, with the corporation tax increasing to 22% for us and then 25% for us in FY 2024, that will clearly weigh heavily on the EPS growth. Over on slide eight, we've set out our ROCE and ROIC calculations. I think the key thing to draw out of this slide is that this really demonstrates the capital light model that we have. We're able to consistently generate a high return over a number of years. You can see it does dip very slightly in certain periods, and that's really driven by acquisitions. It then picks back up again once those acquisitions are bedded in.
We've amortized some of the other intangibles and paid down some of the debt. But going forward, you know, this sort of level, high twenties, we see no reason why we're able to deliver this, this kind of return consistently going forward. Jumping onto the balance sheet, I'm pleased to say that we had a pre-IFRS 16 net cash of GBP 22.2 million. So that's compared to a net debt position at the end of the last year of GBP 13.7 million, and on an IFRS 16 basis, that was GBP 5.7 million of cash versus net debt of GBP 29.3 million at the end of last year. Also pleased to say that we've now fully repaid the term loan that we took out in 2018.
This was a GBP 35 million, four-year term loan that we took out in 2018 to part-fund the acquisition of QTS. We made the last installment on that in March. During the year, we announced earlier in April, and talked about it in our interims, that we completed the buy-in of all of the remaining liabilities of the Amco pension scheme. That's alongside what we did in November 2020 with the Lovell scheme. I'm delighted that we've further de-risked the balance sheet by completing the buy-in of both of our pension schemes. And what we'd look to do over time now is hopefully move to a position of buyout so in the coming years. We've continued to maintain our provision against our discontinued historic liabilities in Allenbuild.
And also pleased to say that post the year-end, we've refinanced our banking facilities. We put in place a new increased RCF facility till November 2026 and introduced a new bank into our syndicate, which gives us significant acquisition firepower going forwards. Flipping to slide 10, we set out our cash flow bridge here. I'm really quite pleased to say that there's not an awful lot to comment on on this slide. What it's doing is just bridging us from GBP 13.7 million net debt. You can see a significant profit coming in during the course of the year, a very small working capital movement, so largely flat on the working capital. And then we've got CapEx, dividends, and tax, which are the three big reductions in cash.
Other is HP movements, and finally, we have a little bit of a cash outflow related to discontinued activities. So this is relating to the settlement of two claims, for Allenbuild and the legal professional fees that, that sat around, managing those claims. That gets us to our net cash position at this year-end of GBP 20.2 million, as I already mentioned. On slide 11, we set out for the first time our free cash flow conversion charts, and pleased to say that what we're seeing is a, is a significant improvement in our free cash flow over the last couple of years.
It's important to note that 2020 and 2021 need to be looked at on average, and the reason for that is that in 2020, we deferred GBP 17 million of VAT, which we then had to repay in 2021 as a consequence of COVID. So what that did was it artificially increased the free cash flow in 2020 and reduced 2021 performance, hence why you need to look at them on average. The real improvement over the last few years is principally driven by the fact that we're not having to make these significant contributions into our pension schemes anymore.
I think going forward, there's no reason why the sort of combined 2021 picture and the 2022 number of sort of, you know, 80%-90% free cash flow, free cash flow conversion cannot be replicated in future years. This is a graph we've been putting in our, in our decks for some time now. It shows our EPS progression over, over the last number of years and various acquisitions that we've made. We're pleased to say that we've generated an 18% compound annual growth rate on EPS since 2011. You can see all of our acquisitions there, including the new latest acquisitions we completed yesterday, which is Enisca, which Paul will talk about more in the environmental section of his report.
A couple of quick slides around acquisitions, and we're not going to spend a lot of time talking about these, but really what we're just trying to do here is just demonstrate the model to people who are relatively new to the story. And what we're saying is, over the same period as you saw on the previous slide, we've tried to demonstrate how the revenue has progressed from where we were in 2010 to where we are this year, and what's made, what's made where that has come from.
As you can see, a big chunk of that has been bought in through acquisitions, and a fairly large chunk, 36%, has come through organic revenue growth, and very much the same on the profit side, albeit a slightly better proportion coming from organic growth in terms of profit. And the reason for that is margin improvement we've seen across the group over a number of years. I think what it really demonstrates is the model. It's the mix that we have. It's a combination of growing business organically and making these earnings-enhancing complementary acquisitions that we've managed to consistently do over a number of years now.
More specifically, on the next slide, we've put the performance of some of our more recent acquisitions, and as you can see, all of these businesses have improved their performance since we acquired them. Clearly, QTS has improved the most, but we've owned it the longest, and what I'd expect to see over the coming years is a similar chart for Carnell and for Browne, as they've spent longer time under our ownership. In terms of our acquisition criteria, it's really unchanged, and these are set out at the bottom right of the page here. We're looking for more businesses that display the same characteristics as the businesses we already have within the group.
We're looking across all of our existing sectors, and I guess the one new sector that we'd be very keen to invest in is transmission and distribution. We see a lot of opportunity in that, in that market as we, as the U.K.'s transmission and distribution network needs to be reconfigured to deal with the way we're going to be generating and using power over the next 20-25 years.
Thank you, Sean. So over the page, we're going to take a bit of a closer look at each of our five operating sectors. I'm going to start with rail, which is on slide 16. Rail represents about 40%-45% of total group revenues, operating margins typically 9% in this segment, and we're currently engaged via over 90 frameworks. We're operating in the final year of the latest control period cycle, CP6, which ends in March 2024. And as anticipated, as we move through that five-year cycle, we have seized growth opportunities to broaden our offering into this market. Our national multidisciplinary rail offering is now very appealing.
We've strengthened our rail position by firstly securing two-year extensions on both our renewal and CAM, our Civils Asset Management, frameworks in our largest regions, in LNE and across Scotland. We've broadened our customer base by securing work for Transport for Wales, and we're now operational on the Transp ennine Upgrade program, and successfully building our reputation in overhead line electrification market, now engaged in the Northwest, in Scotland, and on the Midland Main Line Electrification Program. And on that point, rail electrification is fundamental to the U.K.'s decarbonization agenda, involving over 15,000 single track kilometers to be electrified by 2040, a multi-billion pound commitment, and therefore, a key future target for Renew and its brands.
We continue to invest in innovative solutions to deliver routine operations, and this will be a key future feature of our value-enhancing proposition as we move forward. In summary, rail is in a pretty good position with lots of growth opportunity ahead as we approach CP7 and beyond. Moving to infrastructure on slide 17, this is where we report our highways, our telecommunications, and our aviation activities. These represent about 20% of total group revenues. Operating margins are typically around 6%, and we currently have around 50 framework contracts covering these three segments. In highways, we remain focused on the strategic highway network. We're in year three of the current RIS 2 control period cycle, where National Highways were allocated just over GBP 24 billion.
We hold five lots on the new SDF frameworks, the Scheme Delivery Frameworks, where we're delivering a range of services, including civil engineering, road restraints, and drainage. Following a group collaboration, two of our brands are now formed the second largest national provider of road restraint systems, so an important example of where collaboration across Renew can work well. Turning to wireless telecoms, there's an estimated GBP 30 billion program of investment to deliver gigabit speeds nationally. This includes the contribution from 5G, the piece that we are interested and focused on. We've built an extremely strong position as a leading acquisition, design, and construction provider of services into the mobile telecommunication market.
This year, we have delivered our highest volume of work since we entered this market in 2014, and this positive momentum prevails as we commence another year. We now have a very broad portfolio of frameworks working for all of the U.K. network operators. Finally, in aviation, workflow via the MAG five-year GBP 700 million civil framework that we announced earlier in the year, the Manchester Airports Group, responsible for Manchester, Stansted, and East Midlands. It's been a little slow to get into momentum. However, the visibility of opportunities are now improving for medium-sized infrastructure improvement programs as we move into 2023, linked, of course, to growing confidence in the aviation sector. Turning to energy on slide 18. Energy represents about 10% of total group revenues.
Operating margins are typically 6%. In this segment, we're currently engaged by over 20 framework contracts. The sector is dominated by work in the U.K. civil nuclear program. The vast majority of the services we provide are associated with non-discretionary, high hazard risk reduction and decommissioning, the cleanup program, underpinned by the Nuclear Decommissioning Authority's GBP 3 billion annual commitment and a life estimate of GBP 124 billion. Over 75% of this annual commitment continues to be dedicated to the operation at Sellafield, where we've operated for over 75 years, and where demand continues to grow for our range of very specialist engineering services, including supply and manufacture of high-integrity nuclear-grade components.
Sellafield are currently also committed to a new program of work, the project partnership program, estimated at over GBP 7 billion in investment over the next 20 years, a suite of new assets to be constructed effectively to deal with the waste, and we're making good progress in positioning the business for the associated growth opportunities. And in line with the strategic objective, we've successfully expanded our nuclear client base that now includes Hinkley Point C, Dounreay, Springfields, the Low Level Waste Repository up in the North West at Drigg, and following an appointment to the framework with Aldermaston, now live in delivering some schemes at Aldermaston. And in the longer term, the Autumn Statement also confirmed a key commitment to Sizewell C as well as the SMR program, the Small Modular Reactor program, which has now got development funding.
Outside of nuclear and conventional energy, we are seeing growth in demand for our specialist hydro tunnel maintenance and renewal services with a number of, significant live schemes ongoing. And the final point I would make in energy is some progress, that we are pleased to report in electric vehicle charging, infrastructure across the U.K. We also have ICP, Independent Connection Provision capability. The stimulus here is helped by the GBP 950 million Rapid Charging Fund that was committed. Our route to market has been successful. We're now appointed by a number of large vehicle fleet owners, and we see this as an important route as this program gathers momentum.
Our fourth engineering strand on slide 19, our environmental services, representing about 20% of total group revenues, with operating margins again around 6%, over 40 framework contracts across these sectors. We describe our strands in environmental as flood alleviation, specialist restoration, and in water. Flood resilience remains a national priority, with a GBP 5.2 billion commitment over the next six years. Our client base includes the Environment Agency, Canal & River Trust, Scottish Canals, and Natural Resources Wales, and we see significant growth opportunity ahead in the long term linked to climate change. In specialist restoration, we continue to target new and emerging opportunities at the parliamentary estate, Victoria Tower and Lords' Roof being examples of key target contracts. Elsewhere, we're working in Manchester on the town hall, we're working at the Botanic Gardens in Edinburgh, and targeting numerous gasholder remediation programs across the country.
In water, our largest segment, we're in year three of the current asset management program cycle, and workflow is generally exactly as we anticipated it to be at the start of this control period. We have very successfully broadened our customer base through the cycle. We're now engaged in 13 of the 25 U.K. water regions. Browne are now fully integrated and performing ahead of expectation, and we're already focused on the anticipated growth opportunities as we move through to the end of AMP7 and into AMP8, which takes over from 2025. And clearly, we are delighted, as I said in the introduction, to be broadening our service offering through the acquisition of Enisca. So on slide 20, here is Enisca.
This is a company that we've followed for some time, and of course, they are a joint venture partner to one of our existing brands, Browne, who we acquired in March 2021. They are a multidisciplinary water specialist providing MEICA services, mechanical, electrical, instrumentation, control, and automation services. These include design, manufacture, installation, system integration, automation, and control, system expertise. These are services in growing demand across the water sector, and they are complementary to our existing water offering. Enisca will remain an independent brand within the Renew family, but our strategy will involve it working closely with our existing three water brands. We believe this is an ideal time to be broadening our service offering ahead of AMP8 from 2025 and beyond. Our final segment, specialist building, it's non-core. It contributed less than 3% of operating profit.
Last year, revenue was a little down, last year on the previous year. However, the order book is very strong indeed, following a very good run of recent awards. We describe our activities across science, following the completion of the major campaign of work at Hammersmith, we've more recently been appointed by Imperial College London for its DOID, the Department for Infectious Diseases' refurbishment program. In landmark projects, we're working at Lambeth Palace, and more recently appointed to the Natural History Museum, a very specialist campaign of work there. And in high-quality residential in London, this remains untouched by the economic circumstances. Key, as always, in this sector, is maintaining selectivity and risk management. Sean.
Yeah, sure. So moving on to slide 23, which sets out our approach to ESG. I think like many other companies in this area, we're continuing to develop our approach. What we set out here is our Renew Resilience plan, based on our four key commitments, which are take climate action, operate responsibly, build social value, and empower our people. And what we've done in each of these commitments is set out a series of targets, and for a couple of years now, we've been measuring our performance against those targets, and on the subsequent pages, I will talk to you about how we have performed. The other thing to say here is delighted to say that we managed to retain our Green Economy Mark, the London Stock Exchange.
We are one of only a limited number of companies on the exchange that have been awarded this mark. And what that means is that we derive more than 50% of our revenues from green activities. So on to page 24, we'll take climate action. You can see that we've been successful in achieving, improving on all of our targets over the course of the last year. We continue to decarbonize our commercial fleet, and we will continue to do so as more and more models become available and becomes more practical to actually do that. We've gone from 1% to 4% over the course of the last year.
We're moving towards using more green energy tariffs across our businesses, and we continue to have 100% of our company car bands with an electric or hybrid option. And clearly, over time, what we will look to do is to remove the non-electric and hybrid options from the list of options that our staff are able to choose from. Under operations responsibly, pleased to say that we're diverting more waste than ever from landfill, wherever we can. We're up to 99%, exceeding our target, and we continue to improve our safety performance, with the LTIFR down to 0.23%, an improvement on the performance in the previous year.
On build social value, I'm delighted to say that because we had less impact than [commercial] year, we were able to make a really strong improvement versus our performance last year. We had much more engagement in local community projects from our staff, exceeding our target of one day. We're up to 1.13 days on average, and we've attended way more than the 50 STEM events we targeted, actually going to 122, which is up from 15 in the previous year. Really strong progress there, and something we need to continue to build on. On empower our people, an excellent response rate from our employee survey, better than in the previous year.
I'm delighted to say that we've now increased our target for mental health first aiders from one in 50 to one in 20, and in actual fact, we've beaten that target again this year, with one in 16 members of staff being mental health first aiders. On training days, we didn't quite hit our 4.5 days, training days per employee. Again, that was slightly impacted by Omicron, as Paul mentioned earlier, in the first four , five months of the financial year, and we expect that number to improve going into next year.
Thank you, Sean. So in concluding the presentation, let me start with a summary of what we see as the strengths of our investment case. Hopefully, you've already heard why our model is very different to what others operating in our sectors. We have a lower risk profile, given the nature of our services, and the fact that we directly deliver our capabilities. Our record trading is evidence of our ability to withstand the challenges of a global pandemic, and now, of course, significant economic challenge. We have consistently executed to strategy, which has delivered this 18% earnings CAGR over the last 12 years, as Sean illustrated earlier. Our markets have high barriers to new entrants and are underpinned by resilient long-term growth dynamics.
And finally, we remain committed to growing the business in our target markets, both organically and acquisitively, as evidenced in the news this morning, albeit with a very disciplined approach to risk and a well-defined search criteria. And finally, as an outlook, we continue to see compelling long-term growth opportunities across U.K. infrastructure, where the Autumn Statement made a clear commitment to continuous infrastructure investment. Funding is underpinned by national need as well as regulatory obligation, and of course, we see growth opportunities driven by the green infrastructure agenda, the route map to net zero 2050. The resilience of our model is now well tested and well proven. We continue to manage the macroeconomic pressures without any material impact to trading.
Supported by a strong order book, we can report positive momentum as we move into a new financial year, and we very much look forward, with confidence, to delivering further successful growth. Thank you for listening.