You’re out of free articles.
Log in
To continue reading, log in to your account.
Create a Free Account
To unlock more free articles, please create a free account.
Sign In or Create an Account.
By continuing, you agree to the Terms of Service and acknowledge our Privacy Policy
Welcome to Heatmap
Thank you for registering with Heatmap. Climate change is one of the greatest challenges of our lives, a force reshaping our economy, our politics, and our culture. We hope to be your trusted, friendly, and insightful guide to that transformation. Please enjoy your free articles. You can check your profile here .
subscribe to get Unlimited access
Offer for a Heatmap News Unlimited Access subscription; please note that your subscription will renew automatically unless you cancel prior to renewal. Cancellation takes effect at the end of your current billing period. We will let you know in advance of any price changes. Taxes may apply. Offer terms are subject to change.
Subscribe to get unlimited Access
Hey, you are out of free articles but you are only a few clicks away from full access. Subscribe below and take advantage of our introductory offer.
subscribe to get Unlimited access
Offer for a Heatmap News Unlimited Access subscription; please note that your subscription will renew automatically unless you cancel prior to renewal. Cancellation takes effect at the end of your current billing period. We will let you know in advance of any price changes. Taxes may apply. Offer terms are subject to change.
Create Your Account
Please Enter Your Password
Forgot your password?
Please enter the email address you use for your account so we can send you a link to reset your password:
A practical guide to using the climate law to get cheaper solar panels, heat pumps, and more.
Today marks the one year anniversary of the Inflation Reduction Act, the biggest investment in tackling climate change the United States has ever made. The law consists of dozens of subsidies to help individuals, households, and businesses adopt clean energy technologies. Many of these solutions will also help people save money on their energy bills, reduce pollution, and improve their resilience to disasters.
But understanding how much funding is available for what, and how to get it, can be pretty confusing. Many Americans are not even aware that these programs exist. A poll conducted by The Washington Post and the University of Maryland in late July found that about 66% of Americans say they have heard “little” or “nothing at all” about the law’s incentives for installing rooftop solar panels, and 77% have heard little or nothing about subsidies for heat pumps. This tracks similar polling that Heatmap conducted last winter, suggesting not much has changed since then.
Below is Heatmap’s guide to the IRA’s incentives for cutting your carbon footprint at home. If you haven’t heard much about how the IRA can help you decarbonize your life, this guide is for you. If you have heard about the available subsidies, but aren’t sure how much they are worth or where to begin, I’ll walk you through it. (And if you’re looking for information about the electric vehicle tax credit, my colleague at Heatmap Robinson Meyer has you covered with this buyer’s guide.)
Get one great climate story in your inbox every day:
There’s funding for almost every solution you can think of to make your home more energy efficient and reduce your fossil fuel use, whether you want to install solar panels, insulate your attic, replace your windows, or buy electric appliances. If you need new wiring or an electrical panel upgrade before you can get heat pumps or solar panels, there’s some money available for that, too.
The IRA created two types of incentives for home energy efficiency improvements: Unlimited tax credits that will lower the amount you owe when you file your taxes, and $8.8 billion in rebates that function as up-front discounts or post-installation refunds on equipment and services.
The tax credits are available now, but the rebates are not. The latter will be administered by states, which must apply for funding and create programs before the money can go out. The Biden administration began accepting applications at the end of July and expects states to begin rolling out their programs later this year or early next.
The home tax credits are available to everyone that owes taxes. The rebates, however, will have income restrictions (more on this later).
“The Inflation Reduction Act is not a limited time offer,” according to Ari Matusiak, the CEO of the nonprofit advocacy group Rewiring America. The rebate programs will only be available until the money runs out, but, again, none of them have started yet. Meanwhile, there’s no limit on how many people can claim the tax credits, and they’ll be available for at least the next decade. That means you don’t need to rush and replace your hot water heater if you have one that works fine. But when it does break down, you’ll have help paying for a replacement.
You might want to hold off on buying new appliances or getting insulation — basically any improvements inside your house. There are tax credits available for a lot of this stuff right now, but you’ll likely be able to stack them with rebates in the future.
However, if you’re thinking of installing solar panels on your roof or getting a backup battery system, there’s no need to wait. The rebates will not cover those technologies.
A few other caveats: There’s a good chance your state, city, or utility already offers rebates or other incentives for many of these solutions. Check with your state’s energy office or your utility to find out what’s available. Also, it can take months to get quotes and line up contractors to get this kind of work done. If you want to be ready when the rebates hit, it’s probably a good idea to do some of the legwork now.
If you do nothing else this year, consider getting a professional home energy audit. This will cost several hundred dollars, depending on where you live, but you’ll be able to get 30% off or up to $150 back under the IRA’s home improvement tax credit. Doing an audit will help you figure out which solutions will give you the biggest bang for your buck, and how to prioritize them once more funding becomes available. The auditor might even be able to explain all of the existing local rebate programs you’re eligible for.
The Internal Revenue Service will allow you to work with any home energy auditor until the end of this year, but beginning in 2024, you must hire an auditor with specific qualifications in order to claim the credit.
Let’s start with what’s inside your home. In addition to an energy audit, the Energy Efficiency Home Improvement Credit offers consumers 30% off the cost (after any other subsidies, and excluding labor) of Energy Star-rated windows and doors, insulation, and air sealing.
There’s a maximum amount you can claim for each type of equipment each year:
$600 for windows
$500 for doors
$1,200 for air sealing and insulation
The Energy Efficiency Home Improvement Credit also covers heat pumps, heat pump water heaters, and electrical panel upgrades, including the cost of installation for those systems. You can get:
$2,000 for heat pumps
$600 for a new electrical panel
Yes, homeowners can only claim up to $3,200 per year under this program until 2032.
Also, one downside to the Energy Efficiency Home Improvement Credit is that it does not carry over. If you spend enough on efficiency to qualify for the full $3,200 in a given year, but you only owe the federal government $2,000 for the year, your bill will go to zero and you will miss out on the remaining $1,200 credit. So it could be worth your while to spread the work out.
The other big consumer-oriented tax credit, the Residential Clean Energy Credit, offers homeowners 30% off the cost of solar panels and solar water heaters. It also covers battery systems, which store energy from the grid or from your solar panels that you can use when there’s a blackout, or sell back to your utility when the grid needs more power.
The subsidy has no limits, so if you spend $35,000 on solar panels and battery storage, including labor, you’ll be eligible for the full 30% refund, or $10,500. The credit can also be rolled over, so if your tax liability that year is only $5,000, you’ll be able to claim more of it the following year, and continue doing so until you’ve received the full value.
Geothermal heating systems are also covered under this credit. (Geothermal heat pumps work similarly to regular heat pumps, but they use the ground as a source and sink for heat, rather than the ambient air.)
Here’s what we know right now. The IRA funded two rebate programs. One, known as the Home Energy Performance-Based Whole House Rebates, will provide discounts to homeowners and landlords based on the amount of energy a home upgrade is predicted to save.
Congress did not specify which energy-saving measures qualify — that’s something state energy offices will decide when they design their programs. But it did cap the total amount each household could receive, based on income. For example, if your household earns under 80% of the area median income, and you make improvements that cut your energy use by 35%, you’ll be eligible for up to $8,000. If your household earns more than that, you can get up to $4,000.
There’s also the High-Efficiency Electric Home Rebate Program, which will provide discounts on specific electric appliances like heat pumps, an induction stove, and an electric clothes dryer, as well as a new electrical panel and wiring. Individual households can get up to $14,000 in discounts under this program, although there are caps on how much is available for each piece of equipment. This money will only be available to low- and moderate-income households, or those earning under 150% of the area median income.
Renters with a household income below 150% of the area median income qualify for rebates on appliances that they should be able to install without permission from their landlords, and that they can take with them if they move. For example, portable appliances like tabletop induction burners, clothes dryers, and window-unit heat pumps are all eligible for rebates.
It’s also worth noting that there is a lot of funding available for multifamily building owners. If you have a good relationship with your landlord, you might want to talk to them about the opportunity to make lasting investments in their property. Under the performance-based rebates program, apartment building owners can get up to $400,000 for energy efficiency projects.
For the most part, yes. But the calculus gets tricky when it comes to heat pumps.
Experts generally agree that no matter where you live, switching from an oil or propane-burning heating system or electric resistance heaters to heat pumps will lower your energy bills. Not so if you’re switching over from natural gas.
Electric heat pumps are three to four times more efficient than natural gas heating systems, but electricity is so much more expensive than gas in some parts of the country that switching from gas to a heat pump can increase your overall bills a bit. Especially if you also electrify your water heater, stove, and clothes dryer.
That being said, Rewiring America estimates that switching from gas to a heat pump will lower bills for about 60% of households. Many utilities offer tools that will help you calculate your bills if you make the switch.
The good news is that all the measures I’ve discussed in this article are expected to cut carbon emissions and pollution, even if most of your region’s electricity still comes from fossil fuels. For some, that might be worth the monthly premium.
Tax Credit #1 offers 30% off the cost of energy audits, windows, doors, insulation, air sealing, heat pumps, electrical panels, with a $3200-per-year allowance and individual item limits.
Tax Credit #2 offers 30% off the cost of solar panels, solar water heaters, batteries, and geothermal heating systems.
Rebate Program #1 will offer discounts on whole-home efficiency upgrades depending on how much they reduce your energy use, with an $8,000 cap for lower-income families and a $4,000 cap for everyone else.
Rebate Program #2 is only for low- and moderate- income households, and will offer discounts on specific electric appliances, with a $14,000 cap.
Read more about the Inflation Reduction Act:
Log in
To continue reading, log in to your account.
Create a Free Account
To unlock more free articles, please create a free account.
If the Senate reconciliation bill gets enacted as written, you’ve got about 92 days left to seal the deal.
If you were thinking about buying or leasing an electric vehicle at some point, you should probably get on it like, right now. Because while it is not guaranteed that the House will approve the budget reconciliation bill that cleared the Senate Tuesday, it is highly likely. Assuming the bill as it’s currently written becomes law, EV tax credits will be gone as of October 1.
The Senate bill guts the subsidies for consumer purchases of electric vehicles, a longstanding goal of the Trump administration. Specifically, it would scrap the 30D tax credit by September 30 of this year, a harsher cut-off than the version of the bill that passed the House, which would have axed the credit by the end of 2025 except for automakers that had sold fewer than 200,000 electric vehicles. The credit as it exists now is worth up to $7,500 for cars with an MSRP below $55,000 (and trucks and sports utility vehicles under $80,000), and, under the Inflation Reduction Act, would have lasted through the end of 2032. The Senate bill also axes the $4,000 used EV tax credit at the end of September.
“Long story short, the credits under the current legislation are only going to be on the books through the end of September,” Corey Cantor, the research director of the Zero Emission Transportation Association, told me. “Now is definitely a good time, if you’re interested in an EV, to look at the market.”
The Senate applied the same strict timeline to credits for clean commercial vehicles, both new and used. For home EV chargers, the tax credit will now expire at the end of June next year.
While EVs were on the road well before the 2022 passage of the Inflation Reduction Act, what the new tax credit did was help build out a truly domestic electric vehicle market, Cantor said. “You have a bunch of refreshed EV models from major automakers,” Cantor told me, including “more affordable models in different segments, and many of them qualify for the credit.”
These include cars produceddomestically by Kia,Hyundai, and Chevrolet. But of course, the biggest winner from the credit is Tesla, whose Model Y was the best-selling car in the world in 2023.
Tesla shares were down over 5.5% in Tuesday afternoon trading, though not just because of Congress. JPMorgan also released an analyst report Monday arguing that the decline in sales seen in the first quarter would accelerate in the second quarter. President Trump, with whom Tesla CEO Elon Musk had an extremely public falling out last month, suggested on social media Monday night that the government efficiency department Musk himself formerly led should “take a good, hard, look” at the subsidies Musk receives across his many businesses. Trump also said that he would “take a look” at Musk’s United States citizenship in response to reporters’ questions about it.
Cantor told me that he expects a surge of consumer attention to the EV market if the bill passes in its current form. “You’ve seen more customers pull their purchase ahead” when subsidies cut-offs are imminent, he said.
But overall, the end of the subsidy is likely to reduce EV sales from their previously expected levels.
Harvard researchers have estimated that the termination of the EV tax credit “would cut the EV share of new vehicle sales in 2030 by 6.0 percentage points,” from 48% of new sales by 2030 to 42%. Combined with other Trump initiatives such as terminating the National Electric Vehicle Infrastructure program for publicly funded chargers (currently being litigated) and eliminating California’s waiver under the Clean Air Act that allowed it to set tighter vehicle emissions standards, the share of new car sales that are electric could fall to 32% in 2030.
But not all government support for electric vehicles will end by October 1, even if the bill gets the president’s signature in its current form.
“It’s important for consumers to know there are many states that offer subsidies, such as New York, and Colorado,” Cantor told me. That also goes for California, New Jersey, Nevada, and New Mexico. You can find the full list here.
Editor’s note: This story has been edited to include a higher cost limit for trucks and SUVs.
Excise tax is out, foreign sourcing rules are in.
After more than three days of stops and starts on the Senate floor, Congress’ upper chamber finally passed its version of Trump’s One Big Beautiful Bill Act Tuesday morning, sending the tax package back to the House in hopes of delivering it to Trump by the July 4 holiday, as promised.
An amendment brought by Senators Joni Ernst and Chuck Grassley of Iowa and Lisa Murkowski of Alaska that would have more gradually phased down the tax credits for wind and solar rather than abruptly cutting them off was never brought to the floor. Instead, Murkowski struck a deal with the Senate leadership designed to secure her vote that accomplished some of her other priorities, including funding for rural hospitals, while also killing an excise tax on renewables that had only just been stuffed into the bill over the weekend.
The new tax on wind and solar would have driven up development costs by as much as 20% — a prospect that industry groups said would “kill” investment altogether. But even without the tax, the Senate’s bill would gum up the works for clean energy projects across the spectrum due to new phase-out schedules for tax credits and fast-approaching deadlines to meet complex foreign sourcing rules. While more projects will likely be built under this version than the previous one, the basic outcomes haven’t changed: higher energy costs, project delays, lost jobs, and ceding leadership in artificial intelligence and manufacturing to China.
"This bill will hit Americans hard, terminating credits that have helped families lower their energy and transportation costs, shrinking demand for American-made advanced energy technologies, and squeezing new domestic energy production at a time of rising demand and prices,” Heather O’Neill, the CEO and president of the trade group Advanced Energy United, said in a statement Tuesday. “The advanced energy industry will endure, but the downstream effects of these rollbacks and punitive policies will be felt by American families and businesses for years to come.”
Here’s what’s in the final Senate bill.
The final Senate bill bifurcates the previously technology-neutral tax credits for clean electricity into two categories with entirely different rules and timelines — wind and solar versus everything else.
Tax credits for wind and solar farms would end abruptly with no phase-out period, but the bill includes a significant safe harbor for projects that are already under construction or close to breaking ground. As long as a project starts construction within 12 months of the bill’s passage, it will be able to claim the tax credits as originally laid out in the Inflation Reduction Act. All other projects must be “placed in service,” i.e. begin operating, by the start of 2028 to qualify.
That means if Trump signs the bill into law on July 4, wind and solar developers will have until July 4 of 2026 to “start construction.” Otherwise, they will have less than a year and a half to bring their projects online and still qualify for the credits.
Meanwhile, all other sources of zero-emissions electricity, including batteries, advanced nuclear, geothermal, and hydropower, will be able to continue claiming the tax credits for nearly a decade. The credits would start phasing down for projects that start construction in 2034 and terminate in 2036.
While there are some potential wins in the bill for clean energy development, many of the safe harbored projects will still be subject to complex foreign sourcing rules that may prove too much of a burden to meet.
The bill requires that any zero-emissions electricity or advanced manufacturing project that starts construction after December of this year abide by strict new “foreign entities of concern,” or FEOC rules in order to be eligible for tax credits. The rules penalize companies for having financial or material connections to people or businesses that are “owned by, controlled by, or subject to the jurisdiction or direction of” any of four countries — Russia, Iran, North Korea, and most importantly for clean energy technology, China.
As with the text that came out of the Senate Finance committee, the text in the final bill would phase in supply chain restrictions, requiring project developers and manufacturers to use fewer and fewer Chinese-sourced inputs over time. For clean electricity projects starting construction next year, 40% of the value of the materials used in the project must be free of ties to a FEOC. By 2030, the threshold would rise to 60%. Energy storage facilities are subject to a more aggressive timeline and would be required to prove that 55% of the project materials are non-FEOC in 2026, rising to 75% by 2030. Each covered advanced manufacturing technology gets its own specific FEOC benchmarks.
Unlike the text from the Finance Committee, however, the final text includes a clear exception for developers who already have procurement contracts in place prior to the bill’s enactment. If a solar developer has already signed a contract to get its cells from a Chinese company, for example, it could exempt that cost from the calculation. That would make it easier for companies further along in the development process to comply with the eligibility rules.
That said, these materials sourcing rules come on top of strict ownership and licensing rules likely to block more than 100 existing and planned solar and battery factories with partial Chinese ownership or licensing deals with Chinese firms from receiving the tax credits, per a BloombergNEF analysis I reported on previously.
Once again, the details of how any of this will work — and whether it will, in fact, be “workable” — will depend heavily on guidance written by the Treasury department. That not only gives the Trump administration significant discretion over the rules, it also assumes that the nTreasury department, which is now severely understaffed after Trump’s efficiency department cleaned house earlier this year, will actually have the bandwidth to write them. Without Treasury guidance, developers may not have the cost certainty they need to continue moving forward on projects.
Up until today, the Senate and House looked poised to destroy the business model for companies like Sunrun that lease rooftop solar installations to homeowners and businesses by cutting them off from the investment tax credit, which can bring down the cost of a solar array by as much as 70%. The final Senate bill, however, got rid of this provision and replaced it with a much more narrow version.
Now, the only “leasing” schemes that are barred from claiming tax credits are those for solar water heaters and small wind installations. Companies that lease solar panels, batteries, fuel cells, and geothermal heating equipment are still eligible. SunRun’s stock jumped nearly 10% on Tuesday.
Other than the new FEOC rules, which will have truly existential consequences for a great many projects, there aren’t many changes to the advanced manufacturing tax credit, or 45X, than in previous versions of the bill. The OBBBA would create a new phase-out schedule for critical mineral producers claiming the tax credit that begins in 2031. Previously, critical minerals were set to be eligible indefinitely. It would also terminate the credit for wind energy components early, in 2028.
One significant change from the Senate Finance text is that the bill would allow vertically integrated companies to stack the tax credit for multiple components.
But perhaps the biggest change, which was introduced last weekend, is a twisted new definition of “critical mineral” that allows metallurgical coal — the type of coal used in steelmaking — to qualify for the tax credit. As my colleague Matthew Zeitlin wrote, most of the metallurgical coal the U.S. produces is exported, meaning this subsidy will mostly help other countries produce cheaper steel.
It looks like the hydrogen industry’s intense lobbying efforts finally paid off: The final Senate bill is the first text we’ve seen since this process began in May that would extend the lifespan of the tax credit for clean hydrogen production. Now, projects that begin construction before January 1, 2028 will still qualify for the credit. This is shorter than the Inflation Reduction Act’s 2033 cut-off, but much longer than the end-of-year cliff earlier versions of the bill would have imposed.
The tax credits for electric vehicles and energy efficiency building improvements would end almost immediately. Consumers will have to purchase or lease a new or used EV before September 30, 2025, in order to benefit. There would be a slightly longer lead time to get an EV charger installed, but that credit (30C) would expire on June 30, 2026.
Meanwhile, energy efficiency upgrades such as installing a heat pump or better-insulated windows and doors would have to be completed by the end of this year in order to qualify. Same goes for self-financed rooftop solar. The tax credit for newly built energy efficiency homes would expire on June 30, 2026.
The bill would make similar changes to the carbon sequestration (45Q) and clean fuels (45Z) tax credits as previous versions, boosting the credit amount for carbon capture projects that do enhanced oil recovery, and extending the clean fuels credit to corn ethanol producers.
The House Rules Committee met on Tuesday afternoon shortly after the Senate vote to deliberate on whether to send it to the House floor, and is still debating as of press time. As of this writing, Rules members Ralph Norman and Chip Roy have said they’ll vote against it.
On sparring in the Senate, NEPA rules, and taxing first-class flyers
Current conditions: A hurricane warning is in effect for Mexico as the Category 1 storm Flossie approaches • More than 50,000 people have been forced to flee wildfires raging in Turkey • Heavy rain caused flash floods and landslides near a mountain resort in northern Italy during peak tourist season.
Senate lawmakers’ vote-a-rama on the GOP tax and budget megabill dragged into Monday night and continues Tuesday. Republicans only have three votes to lose if they want to get the bill through the chamber and send it to the House. Already Senators Thom Tillis and Rand Paul are expected to vote against it, and there are a few more holdouts for whom clean energy appears to be one sticking point. Senator Lisa Murkowski of Alaska, for example, has put forward an amendment (together with Iowa Senators Joni Ernst and Chuck Grassley) that would eliminate the new renewables excise tax, and phase out tax credits for solar and wind gradually (by 2028) rather than immediately, as proposed in the original bill. “I don’t want us to backslide on the clean energy credits,” Murkowski told reporters Monday. E&E News reported that the amendment could be considered on a simple majority threshold. (As an aside: If you’re wondering why wind and solar need tax credits if they’re so cheap, as clean energy advocates often emphasize, Heatmap’s Emily Pontecorvo has a nice explainer worth reading.)
At the same time, Utah’s Senator John Curtis has proposed an amendment that tweaks the new excise tax to make it more “flexible.” The amendments are “setting up a major intra-party fight,” Politicoreported, adding that “fiscal hawks on both sides of the Capitol are warning they will oppose the bill if the phase-outs of Inflation Reduction Act provisions are watered down.” Senators have already defeated amendments proposed by Democrats Jeanne Shaheen of New Hampshire and John Hickenlooper of Colorado to defend clean energy and residential solar tax credits, respectively. The session has broken the previous record for most votes in a vote-a-rama, set in 2008, with no end in sight.
The Department of Energy on Monday rolled back most of its regulations relating to the National Environmental Policy Act, or NEPA, and published a new set of guidance procedures in their place. The longstanding NEPA law requires that the government study the environmental impacts of its actions, and in the case of the DOE, this meant things like permitting and public lands management. In a press release outlining the changes, the agency said it was “fixing the broken permitting process and delivering on President Trump’s pledge to unleash American energy dominance and accelerate critical energy infrastructure.” Secretary of Energy Chris Wright said the agency was cutting red tape to end permitting paralysis. “Build, baby, build!” he said.
Nearly 300 employees of the Environmental Protection Agency signed a letter addressed to EPA head Lee Zeldin declaring their dissent toward the Trump administration’s policies. The letter accuses the administration of:
“Going forward, you have the opportunity to correct course,” the letter states. “Should you choose to do so, we stand ready to support your efforts to fulfill EPA’s mission.” It’s signed by more than 420 people, 270 being EPA workers. Many of them asked to sign anonymously. In a statement to The New York Times, EPA spokesperson Carolyn Horlan said “the Trump EPA will continue to work with states, tribes and communities to advance the agency’s core mission of protecting human health and the environment and administrator Zeldin’s Powering the Great American Comeback Initiative, which includes providing clean air, land and water for EVERY American.”
At the fourth International Conference on Financing for Development taking place in Spain this week, a group of eight countries including France and Spain announced they’re banding together in an effort to tax first- and business-class flyers as well as private jets to raise money for climate mitigation and sustainable development. “The aim is to help improve green taxation and foster international solidarity by promoting more progressive and harmonised tax systems,” the office of Spanish Prime Minister Pedro Sanchez said in a statement. Other countries in the coalition include Kenya, Barbados, Somalia, Benin, Sierra Leone, and Antigua & Barbuda. The group said it will “work towards COP30 on a better contribution of the aviation sector to fair transitions and resilience.” Wopke Hoekstra, who heads up the European Commission for Climate, called for other countries to join the group in the lead-up to COP30 in November.
In case you missed it: Google announced on Monday that it intends to buy fusion energy from nuclear startup Commonwealth Fusion Systems. Of course, CFS will have to crack commercial-scale fusion first (minor detail!), but as The Wall Street Journal noted, the news is significant because it is “the first direct deal between a customer and a fusion energy company.” Google will buy 200 megawatts of energy supplied by CFS’s ARC plant in Virginia. “It’s a pretty big signal to the market that fusion’s coming,” CFS CEO Bob Mumgaard told the Journal. “It’s desirable, and that people are gonna work together to make it happen.” Google’s head of advanced energy Michael Terrell echoed that sentiment, saying the company hopes this move will “prove out and scale a promising pathway toward commercial fusion power.” CFS, which is backed by Bill Gates’ Breakthrough Energy Ventures, aims to produce commercial fusion energy in the 2030s.
All the public property owned by Britain’s King Charles earned a net profit of £1.15 billion ($1.58 billion) last year. The biggest source of income? Offshore wind leases.