Today many homes get heating and hot water from a combi boiler, this medium sized wall mounted box provides for an average three bed house. Switch to a heat pump and we now need to add a hot water tank and possibly a buffer tank, each of these also need an expansion tank. For the same house these could now take a space more like a small room.
I’m fortunate that we have a room at the back of the house that was being used for storage that we have been able to repurpose as a utility and plant room, for others this is going to be a more significant challenge.
This is further exacerbated by the tendency of the heat pump industry to conservatively specify everything in fear of providing something that doesn’t meet the needs of minus seven degrees in the depths of winter. My own system has been over spec’d at all stages – two heat pumps, wide pipes, and larger radiators – comforting, but large.
Much deeper innovation is needed.
Firstly, we need far better data on the real-world performance of heat pumps in many different homes. Heat Pump Monitor provides great insight its data needs to be scaled up and used in all installations.
Through Home Assistant I now have months of near real time data on the heat loss from my house. Combining this data across thousands of homes will provide even greater insight into real world operating conditions. Claude has used this data to estimate a heat loss for my house of 8.5 kW on a minus 2 winter day, my heat pumps will provide 24 kW.
Systems need to be designed for compactness. Why have two almost identical tanks holding water at the same temperature when perhaps one tank could do both jobs? What can be rationalised and simplified?
As with so many technologies before, the winner won’t necessarily be the most efficient, in the case of heat pumps it may be the smallest and most easily installed system.
The implications on government policy need to be addressed, this is not just about making heat pumps more efficient or cheaper. Policy needs to support smaller compact systems that fit into the space that people already have for their gas boilers.
The next frontier is not higher efficiency, or what colour and shape to have the external fan box, it’s shrinking what gets installed inside the home. British homes are amongst the smallest in the developed world, new homes are now around 75 m2, when historically we had 100 m2, with most of Europe larger and the US twice the size.
A system that fits in a small cupboard will unlock more decarbonisation than a larger grant.
