Does Solar Increase Commercial Property Value?

The honest answer is: not directly, and not on its own. A solar array does not add a fixed number to a valuation the way a roof replacement or a new lift does. What solar does is feed the three mechanisms that valuers, funders and tenants now price into commercial property — energy performance, certification and disclosed ESG metrics. Where those mechanisms move the rent and the yield, the asset value follows. This post sets out what the green-premium evidence actually shows, where it does not apply, and how a well-engineered solar installation contributes to value rather than just cutting a bill.

What the green-premium data says

The headline figures come from a handful of credible studies, and they are worth quoting precisely because they are routinely mangled.

JLL, analysing BREEAM-certified prime London offices over 2017–2021, found rents associated with green certification around 11.6% higher and capital values around 20.6% higher than comparable non-certified stock. The same work attributed roughly +4.2% rent and +3.7% capital value per EPC band improvement. Knight Frank’s research on London offices put the rental premium for strong sustainability credentials in the range of +3.7% to +12.3%.

Those numbers are real and they are large. They are also narrow.

Read the data honestly

Three caveats sit on every one of those figures, and any owner relying on them for an investment case needs to hold all three.

First, the evidence base is prime central London offices. It does not transfer cleanly to a Midlands trade counter, a regional retail park or a single-let industrial unit. The occupier base in prime London is dominated by corporates with hard net-zero commitments and the budget to pay for compliance; that demand is what creates the premium. Most of the UK’s commercial stock does not face that same tenant pressure yet.

Second, the language matters. These premiums are “associated with” green credentials, not “caused by” them. Better-performing buildings tend to be newer, better-located, better-managed and owned by better-capitalised landlords. Disentangling the contribution of the certificate from everything else that travels with it is genuinely hard, and the studies are careful to say so. Treat the figures as the upper bound of what is achievable in the strongest market, not a default uplift you can underwrite anywhere.

Third, solar is one input to certification, not the certificate itself. A panel array on its own lifts a commercial EPC by roughly one to three bands depending on the starting rating, building fabric and how the generation is counted — never a guaranteed jump. It contributes BREEAM and GRESB points; it does not buy them outright.

The discount is the more reliable story

The more dependable half of the green-premium argument is the brown discount — the penalty for poor performance — because that is now backed by hard regulation rather than soft preference.

Under the Minimum Energy Efficiency Standards (MEES), it has been unlawful since 1 April 2023 to let commercial property in England and Wales below EPC E, including to sitting tenants. That is the binding law today. The government’s interim response of 18 June 2026 proposed a higher bar — EPC B by 2031 for privately rented non-domestic buildings over 1,000 m², only where cost-effective and subject to secondary legislation. It is a proposal, not law, and the earlier “EPC C by 2027” target was scrapped. Even so, the direction is unmistakable, and valuers are already discounting assets that face a costly compliance path.

The stranding numbers explain why. The British Property Federation reported in October 2025 that around 83% of commercial buildings across seven major UK cities sit below EPC B. CBRE put roughly 58% of Central London offices below B. Savills estimated around 185 million sq ft of UK retail at risk on energy grounds. A building that cannot be let, or can only be let at a discount with a remediation overhang, carries that risk straight into its valuation.

Solar does not solve stranding by itself — fabric, glazing and heating usually matter more for the EPC — but it is one of the few interventions that improves the rating, generates income and qualifies for capital allowances at the same time.

How solar feeds the three value mechanisms

For an investor or asset manager, the GRESB line is often the one that matters most. Fund-level ESG scores feed cost of capital, LP reporting and acquisition screening. A measurable on-site renewable contribution, documented and metered, is exactly the kind of evidence that improves a portfolio’s disclosed position. That is where solar quietly earns its keep on the balance sheet rather than just the P&L.

So where does value actually come from

Strip out the marketing and three real value channels remain:

• Income. Self-consumed solar displaces grid electricity at roughly 24–28p/kWh; the savings (or PPA income, if you sell power to a tenant) are a durable cash flow that lifts net operating income. Capitalise that at the building’s yield and you have a direct, defensible value contribution.
• Risk reduction. A higher EPC and a documented renewable contribution reduce the probability of a future MEES overhang, void periods on green-mandated tenants, and forced remediation capex. Lower risk means a tighter yield.
• Marketability. In segments where occupier demand for low-carbon space is real — increasingly logistics and good-quality offices, not just prime London — solar is part of the package that lets the space faster and holds the rent.

None of those is the headline 20.6% number. All of them are more reliable than it.

The owner’s verdict

Does solar increase commercial property value? It increases the things that drive value — energy performance, certification scores, net income and lettability risk — provided the system is sized to the load and the ownership structure puts the income where it belongs. The published premiums are real but specific to prime London; do not underwrite a regional asset on a central-London figure. The brown discount, anchored in MEES law and the stranding data, is the more bankable case. Read both honestly and solar earns its place in the asset plan.

For the full evidence base and the caveats, see our green premium and asset value guide, the MEES and EPC guide for the compliance picture, and the ESG, GRESB and net-zero funds guide for how this lands in investor reporting.

Get the numbers for your asset

A green-premium argument is only as good as the modelling behind it. We size the array to your building’s load, project the EPC band movement and self-consumption, and set out how the income and risk reduction translate into value at your yield. Request a quote and we will run the figures for your specific property.