In a recent interview with Elemental London, former Secretary of State for Energy Security and Net Zero, Grant Shapps, shared why he hasn’t installed a heat pump in his own home:
“My place is a 1930s house with solid walls with a conservatory tacked on the back – exactly the sort of awkward property that shows why fabric first matters. Until the insulation is sorted a heat pump would be like fitting a Rolls-Royce engine to a shopping trolley: impressive, but wildly inefficient.”
Comments like this from the former Energy Secretary on insulation and heat pumps are deeply unhelpful, and factually wrong. This one quote captures everything that’s wrong with the public conversation around heat pumps, and why government-led messaging on decarbonising heat has so far failed to inspire widespread confidence or uptake among homeowners.
The “Fabric First” Misconception
Let’s address the obvious: no one disputes that insulation is important. Insulating lofts, draught-proofing and cavity wall upgrades where possible are all low-hanging fruit and worthwhile measures, and are important irrespective of your heating source. But this idea that you must comprehensively upgrade your insulation before you even think about a heat pump is not only false… it’s actively damaging.
Shapps’ “Rolls-Royce in a shopping trolley” comment is not just inaccurate, it’s reckless, coming from someone who held a brief that included transitioning homes away from fossil fuels. It reinforces the idea that unless your home is a newbuild or a fully retrofitted eco-palace, heat pumps are off the table. That is categorically untrue.
We interact with homeowners every day that have solid wall pre-1940s homes, draughty Victorian terraces and rural farmhouses who are successfully running heat pumps. Many aren’t fully insulated. Some have done modest upgrades, others are still in progress. And yet, they’re getting SCOPs of 3.0 to 4.5. Are the systems perfectly optimised? Not always. But are they “wildly inefficient”? Absolutely not!
Take Graham Hendra’s well-documented case: a 1930s house retrofitted with a 10-year-old Samsung air source heat pump. The property had its original 1970s heating system: copper pipes, standard white radiators and an old Ideal Mexico boiler. No new radiators were fitted. No repiping. No fancy thermostats. The only upgrade was replacing the boiler with the heat pump and swapping the old copper cylinder for a thermal store. Everything else remained… including a conservatory.
The results? Impressive. Heat output was measured both before and after the upgrade, and the data told a clear story. Despite the boiler having a nominal flow temp of 80C, average flow temps during the coldest months were around 51C, already within heat pump territory. Once the system was switched over, a weather compensation curve was used to run the heat pump at 35C flow when it was 15C outside, and 52C at -2C, exactly as a properly designed low-temperature system should operate.
This wasn’t theoretical. It worked in a 1930s house. With existing pipework and radiators. Without any of the catastrophic inefficiencies we’re led to believe are inevitable.
The Real Problem: Misinformation and Poor Design
What causes inefficiency is poor design and installation, not the age or construction of the building. Oversized units, poorly balanced radiators, unnecessary buffers, cycling systems and installers who don’t understand low flow temperatures… these are the real culprits. And unfortunately, they’re everywhere, something Mr Shapps could have learned by spending ten minutes browsing the Renewable Heating Hub forums.
The idea that “the technology works brilliantly in the right setting” might sound reasonable, but it’s dangerously vague. What is the right setting? According to Shapps, it’s clearly not a typical British home. So by implication, most people should wait. That message (coming from someone in his former position) undermines the progress many good installers and informed homeowners are making every day.
What Shapps Could Have Said
Instead of trotting out tired myths, Shapps could have used his platform to say like: “My house isn’t straightforward (like many in the UK) but we’re exploring how a heat pump could work here, and I’ll share what we learn.”
That would have shown leadership. That would have given people confidence. That would have sent a signal that complexity is not the enemy of progress… it’s just something to design around. But no. We got the shopping trolley metaphor instead.
If you’re reading this and you live in an older, solid-wall property, don’t be put off. Get a proper room-by-room heat loss calculation, work with a reputable installer and don’t let someone else’s lack of imagination become your barrier to progress.
Heat pumps do work in older homes. The problem isn’t your house, it’s the narrative. And until public figures stop repeating half-baked takes like Shapps’ and start championing real-world solutions, we’ll keep spinning our wheels.
And I bet that any of the installers on the Renewable Heating Hub recommended list could install an efficient system at Mr. Shapps’ house.
