Installer guide · 16 min read

Carbon Credits, Carbon Offsetting and Commercial Solar: How to Win the Carbon Conversation

Short answer: when a business asks whether solar will earn it carbon credits, the honest answer in the UK is almost always no. What solar does is cut the emissions from the electricity it would otherwise buy, its scope 2 emissions, and that is a real reduction it can report. That beats buying offsets, which UK government guidance treats as a separate line for emissions a business has not been able to cut. Sell the reduction with the workings, never a credit.

A guide for installers and their sales teams, checked against the primary sources listed at the end on 6 November 2026. It is not reporting or legal advice: the customer's own reporting adviser signs off their figures.

Why businesses ask about carbon credits and offsetting

Carbon comes up on commercial solar calls because someone inside the business has been asked for a number. Finding out who asked, and why, tells you what the proposal has to answer:

"Can we get carbon credits for this?" is usually shorthand for "will this help with the carbon number we have to produce?". The answer to the second question is yes. The answer to the first is the next two sections.

Carbon credits in plain English: compliance and voluntary markets

A carbon credit represents one tonne of carbon dioxide equivalent (CO2e) reduced or removed by a project, which a buyer can use to compensate for its own emissions. There are two kinds of market.

Compliance markets are set by law. The UK's is the UK Emissions Trading Scheme, a cap and trade scheme that applies to power generation, energy intensive industry, aviation and, from 1 July 2026, domestic maritime. Covered operators must surrender allowances for their emissions each year. An ordinary business with a warehouse roof is not in it.

Voluntary markets are where businesses buy credits by choice. In the UK the best known are the Woodland Carbon Code, which describes itself as the UK's government-backed standard for new woodland, and the Peatland Code for peatland restoration, run by the IUCN UK Peatland Programme. The government's 2025 consultation on voluntary carbon markets points to these two codes as UK leadership in domestic voluntary markets. Neither covers solar, and we found no UK code that issues credits for rooftop solar. Internationally the large standards are Verra's Verified Carbon Standard and Gold Standard.

Can a UK business earn carbon credits from its own solar?

We checked each route a customer might have heard about against its own rules. None gives an ordinary UK business a practical way to sell credits from its roof:

There is a second problem even where a route exists. A credit is a claim on a tonne that the buyer gets to use. A business that sold credits from its solar would be selling the very reduction it wanted for its own report, so it could not count the same tonne again. For most customers, keeping the reduction is worth more than any credit.

Say it plainly on the call: "Solar won't earn you carbon credits you can sell, but it will cut the emissions you report, and here is by how much." Customers trust the installer who tells them that.

What solar actually does: it cuts scope 2 emissions

The GHG Protocol, the standard most reporting follows, sorts emissions into scopes. Scope 1 is fuel burned on site (gas boilers, vehicles). Scope 2 is purchased electricity, heat and cooling. Every kWh a business makes on its roof and uses itself is a kWh it no longer buys from the grid, so its scope 2 emissions fall. The solar panels themselves burn nothing, so there is nothing to add to scope 1.

The figure to use is the UK government's greenhouse gas conversion factor for company reporting, published by DESNZ every year. For 2026 the factor for UK electricity (scope 2) is 0.13096 kg CO2e per kWh. In 2025 it was 0.17700. It falls as the grid gets cleaner, which matters for how you present figures over time (see below). There is a separate scope 3 factor for transmission and distribution losses, 0.01299 kg CO2e per kWh in 2026, which some customers report too.

A worked example in tonnes

An illustration, not a real site: a 100 kWp system on a business roof, producing about 1,000 kWh per kWp a year, so about 100,000 kWh. Actual yield depends on location, orientation and shading. Only the share used on site reduces the electricity the business buys:

The sum is simple: kWh used on site × 0.13096 ÷ 1,000 = tonnes CO2e. The same 100,000 kWh at the 2025 factor would have been 17.7 tonnes. That is why a proposal should name the factor's year, and why "13.1 tonnes a year for 25 years" would overclaim: each year's report uses that year's factor.

Carbon offsetting vs reducing: why solar comes first

Carbon offsetting means buying credits from a project somewhere else, such as new UK woodland, to compensate for emissions the business still has. The official position is clear about the order of things:

• The UK government's first principle for voluntary carbon and nature market integrity says that, in line with the mitigation hierarchy, companies should make every reasonable effort to minimise their own impacts before using credits, and that credits should only be used in addition to ambitious action within value chains.
• The government's environmental reporting guidelines say offsets should be listed separately and not accounted for in the reported gross emissions figure. A business can show a net figure, but its gross figure only falls when it actually cuts emissions.
• The Woodland Carbon Code itself talks about using its units to compensate for unavoidable emissions.

Be honest about price as well. The Woodland Carbon Code's price page puts the average reported price of a woodland Pending Issuance Unit for 2025 at £28.32, with a spread of £112.50 between the lowest and highest prices reported (checked 6 November 2026; prices vary and a Pending Issuance Unit is a promise of a future verified unit, not a guaranteed one). At that average, offsetting the 13.1 tonnes in the example would cost roughly £370 a year. So never sell solar as a cheaper tonne. Sell it on the electricity bill, and present the carbon as a real, reportable cut in gross emissions that an offset can never give.

SECR, location-based vs market-based, and REGOs

SECR. Quoted companies, and large unquoted companies and LLPs, report energy and carbon information in their annual reports. A company is large if it meets two of these: turnover over £54 million, balance sheet over £27 million, more than 250 employees (the Companies Act thresholds that SECR follows). Those that used 40 MWh or less in the period are exempt as low energy users.

Location-based and market-based. The GHG Protocol's Scope 2 Guidance has two methods. Location-based uses the average emissions of the grid where the electricity is used, which is the DESNZ factor above. Market-based uses the emissions of the electricity a company has chosen to buy through contracts and certificates. Where those contracts exist, the Protocol asks for both figures. SECR guidance encourages location-based reporting, with a market-based figure alongside it for renewable contracts, stating whether renewable energy is supplied directly, including on-site generation. Solar cuts the location-based figure because the business simply buys less grid electricity.

REGOs. Ofgem issues one Renewable Energy Guarantee of Origin per megawatt hour of eligible renewable output, and their main use is suppliers' fuel mix disclosure. They matter to a customer who reports market-based and buys renewable tariffs. They are not carbon credits, and most rooftop proposals do not need to mention them.

How to put carbon figures in a proposal without overclaiming

Ask early who will use the figure. A finance director writing an SECR report wants kWh and the factor. A bid writer filling in a Carbon Reduction Plan wants scope 1 and 2 tonnes. An owner who just wants to tell customers wants one clear, defensible sentence. Get the electricity data you need for this at the survey: our guide to qualifying commercial solar leads covers bills and half-hourly data, and solar PPAs explains how ownership changes who reports what.

Which businesses care most about carbon

• SECR companies. Large companies already publish their energy use, so you can read it in the directors' report before you call: see the SECR section of our commercial solar prospecting guide.
• Suppliers bidding for big public contracts. Under PPN 006, central government bidders for contracts over £5 million a year provide a Carbon Reduction Plan with scope 1 and 2 emissions. Our commercial solar tenders guide covers the public sector side from the installer's view.
• Suppliers to larger companies. Manufacturers, distributors and logistics firms whose customers ask them for emissions figures.
• Businesses with a public target. If the website or annual report mentions net zero, carbon is already on the board's agenda.

For all of them, carbon is a reason to act now, not the whole case. The bill savings still carry the decision.

Getting in front of these businesses

If you would rather spend your time on surveys than on finding the businesses that are asking these questions, TNW Marketing books pre-qualified commercial solar site meetings with the decision-maker, paid per attended appointment. You only pay for appointments that are actually attended, and any that aren't viable we replace.