Some big changes are afoot concerning how we heat our homes, but what are they?
Currently an estimated 14% of the UK’s carbon emissions come from space heating, which is largely (although not exclusively) powered by natural gas. The government’s drive to retrofit UK homes to reach net-zero includes grants available for heat pumps and a large focus is on electrifying the heating system, but electrification isn’t the only game in town.
There are many exciting and innovative ideas for how we will heat our homes in the future. Let’s take a look at some of the big breakthroughs that have happened lately.
Waste Heat to Warm Homes
The laws of thermodynamics state that all energy eventually ends up as heat. Heat is usually seen as an incidental by-product to either ignore or control, but what if we could harness it? What if heat as a by-product became a way of keeping our homes and businesses warm?
An (admittedly old) study showed that by harnessing extra heat produced by power stations like Drax, the UK could reduce its carbon emissions by 2%, and across the world there are a variety of heat capture initiatives which warm local homes. In Denmark, a crematorium is used to heat local homes, and in Cologne, Germany, sewage provides heat to residents.
For the squeamish among us, a more palatable option might be to use data centres, the background soldiers of the internet, to heat homes. This is exactly the strategy in Switzerland, where company IBM uses the excess heat created by their data centre computers to provide warmth for locals.
A pioneering waste heat initiative in the UK is seeing the use of excess heat from the tube to heat homes, schools and a leisure centre in Islington, North London. The revolutionary Bunhill 2 Energy Centre – established in an unused tube station – has the potential to power over 2000 homes and reduce CO2 emissions by 500 tons per year. If things go well we could soon see many such initiatives in our neighbourhoods.
Hybrid Hydrogen for Low Wind Days
Hydrogen seems like an obvious low-carbon fuel source to use in the UK. Environmentally-friendly hydrogen can be made through electrolysis of water; using electricity to split hydrogen from oxygen, and once burned the only byproduct of hydrogen power is water. The theory goes that the water vapour released by using hydrogen will balance out the removal of water used to create the fuel.
The hydrogen economy could be worth £900 million and provide up to 30% of the UK’s energy by 2050. One of the additional benefits of hydrogen is that it can be used in existing infrastructure which natural gas is used in now.
Hydrogen can also be used in combination with low-carbon electric technology like heat pumps, providing exciting potential for hybrid low-carbon heat systems. This theory is being put into practice in Wales, where the Worcester Bosch boiler in Pembrokeshire has been using H2 fuel when there aren’t enough renewable energy supplies to power heat pumps.
This kind of hydrogen system is an exciting breakthrough as much of the renewable renewable electricity in the UK is to come from wind farms which are subject to supply issues at times. Hydrogen may provide the back up we all need.
Geothermal Gems to Keep us Warm
Geothermal energy – using underground steam to create electricity and heat – is a highly site-specific form of energy production and can’t be done everywhere. In Iceland, a country famous for its volcanoes, hot springs and geysers, 66% of primary energy use comes from geothermal power, heating almost all domestic spaces.
Surely this kind of power isn’t possible in the UK…or is it?
Cornish Lithium, a mining company set to explore metal extraction in the South West for lithium batteries, have the go ahead to explore creating shallow geothermal pools to power local businesses in the region. While in the early stages, this scheme has the potential to massively speed up decarbonisation in the area if it is deemed suitable for use in homes in the future.
Meanwhile, exciting new research in China found that geothermal energy from the shallows of the seabed is relatively easy to extract and is efficient at space heating. Considering the low environmental impact of installation and the UK’s 12,000km of shoreline, we may soon be keeping toasty using the coast.
Is Fusion the Future?
Finally, big news comes out of Oxford as the JET Lab manages to produce the largest ever amount of power from a nuclear fusion reaction. In February 2022, JET, which has been operating for 40-years, produced a successful reaction which generated 11 megawatts of power, enough to boil 60 kettles of water.
Fusion usually takes place in the sun and requires a temperature of 100 million celsius to operate on earth. The reaction, which requires squeezing together two hydrogen molecules, requires so much heat that no material on earth would be able to hold it, and it instead must take place in a donut-shaped magnetic field.
Nuclear fusion produces significantly less radioactive waste than nuclear fission, the current way of powering nuclear plants. The success at JET shows good signs for a similar, larger operation due to start in France soon. If nuclear fusion is cracked it will provide the unlimited low-carbon energy. However the snag is most experts believe it will not be ready for widespread use before 2050, meaning we must decarbonise our economy without it.