A landlord with a portfolio of properties in Nottingham has raised a question that will resonate with thousands of others: can cheap, plug-in solar panels actually help improve an Energy Performance Certificate rating, or are they just a nice-to-have that assessors will ignore? The query, posted on landlord forum Property118, gets to the heart of a problem facing the private rented sector as the government's proposed 2030 deadline for EPC C compliance edges closer.
The landlord in question is already working through the process of bringing their properties up to a C rating and had spotted that plug-in solar panels, described as a newly emerging product, might offer a lower-cost route to improving energy performance than more disruptive works like insulation upgrades, new boilers or double glazing. The trouble is nobody seems entirely sure yet whether these devices actually move the needle on an EPC assessment, or how an assessor would even record them.
Why this matters beyond one Nottingham landlord
EPC compliance has become one of the biggest financial anxieties in the buy-to-let sector. Landlords with older or harder-to-treat properties are weighing up costly options such as external wall insulation, replacement heating systems or full rewiring, all of which can run into thousands of pounds per property and often require access, planning consideration, or temporary decanting of tenants. Against that backdrop, a plug-in device that a landlord could fit in an afternoon looks very appealing.
But EPC assessments follow a standardised methodology, and it is not yet clear that assessors have a straightforward way of crediting plug-in solar generation in the same way they would credit a permanently wired solar PV installation. This is exactly the kind of grey area that tends to produce expensive mistakes: landlords spending money on a fix that never shows up in the final certificate. Until there is clearer guidance, or feedback from landlords who have actually tried it and had it assessed, this remains a genuine unknown rather than a proven shortcut.
The bigger compliance decision landlords are facing
What this discussion really reflects is the pressure landlords are under to find the cheapest possible path to compliance, whatever the eventual deadline turns out to be. For some, that will mean a scattergun approach of smaller, lower-cost interventions like LED lighting, loft top-ups and, potentially, plug-in solar, in the hope they collectively nudge a rating up a band. For others, particularly those with older stock that is well below a D or E, a more substantial refurbishment will be unavoidable.
That is where the financing question becomes real. A full retrofit, including new heating, insulation and glazing across a property or a small portfolio, can be a significant outlay, and mortgage lenders do not always fund works of that scale easily, particularly on a tight timescale. Landlords converting properties into HMOs while carrying out this kind of upgrade work sometimes look at short-term finance to bridge the gap between buying, renovating and refinancing or letting; those weighing that route can read more about bridging loans for HMO conversion projects and how they're typically structured.
What to do while the picture is still unclear
For now, landlords considering plug-in solar as part of an EPC strategy would be sensible to treat it as speculative rather than guaranteed. It's worth asking a domestic energy assessor directly, before spending anything, whether the specific product being considered would actually register in an assessment. Relying on forum chatter or manufacturer marketing claims alone is risky when the cost of getting it wrong is a wasted purchase and no improvement in rating.
It's also worth remembering that EPC policy for the private rented sector has shifted before and could shift again, so decisions should be based on current confirmed requirements rather than assumptions about exactly when or how a 2030 deadline will apply. Landlords with larger portfolios or properties needing more substantial work may find it more efficient to plan a proper retrofit programme rather than chase piecemeal fixes property by property.
