The potential for hybrid heat pumps using electricity most of the time and then hydrogen to meet peak demand on cold winter days has been a “light bulb moment”, the Committee on Climate Change said.
While the Government has had success in cutting emissions from electricity, carbon from heating buildings has been a much more intractable problem because of the impact on people’s lives of changing how homes are heated.
But a new report from the Committee said installing hybrid heat pumps for buildings on the gas grid, along with boosting energy efficiency and making new homes more efficient, could cut emissions to near zero by 2050.
Hybrid versions of heat pumps, which use the UK’s increasingly low-carbon electricity to extract heat from the air, can be retrofitted around existing boilers, and do not require changes to radiators.
The system would use gas on the coldest winter days to ensure the same performance as existing heating systems, while cutting emissions in the near term, the report said.
The remaining gas supply could be switched to hydrogen at a later date to almost completely remove fossil fuel use in buildings.
And the use of the hybrid heat pumps would need far less hydrogen than a wholesale switch of the gas grid to the cleaner fuel would require.
It is a system which has been tested in a pilot in Bridgend, South Wales, with positive feedback from households, the committee said.
The report also found hydrogen could play a role in cutting fossil fuels from heavy goods vehicles, industrial processes and to replace gas power to manage peaks in an electricity system with a high amount of renewables.
Hydrogen would be generated from natural gas using technology to permanently capture and store carbon underground, a more cost effective way to scale up hydrogen production than using electricity to create it.
The Committee’s deputy chairwoman Baroness Brown said: “Hybrid heat pumps are the best of both worlds. Heat pumps on their own haven’t been very successful in this country.”
The new analysis has found it would not be a more expensive solution than a full switch of the gas grid to hydrogen or a move over to electrifying heating.
Government must develop a full strategy for removing carbon emissions from heating in the next three years, including clear signals on future use of the gas grid and support for carbon capture and storage, the committee said.
Pilot schemes and public engagement will also be needed to communicate the need to cut carbon from heating and reassure people hydrogen is safe, the report said.
Lord Deben, chairman of the Committee on Climate Change (CCC), said: “The future now rests on Government making a quick decision and fully committing to low-carbon heat within the next three years.
“This is important to achieving the existing 2050 emissions target, but even more important as we consider whether it is possible for the UK to reach ‘net-zero’ emissions in the future.”
A Business Department spokesman said: “As we strive to meet our ambitious climate change targets and deliver value for money, the Government will continue to work with industry and academia to understand the options that hydrogen offers to our future energy system.
“Alongside funding for hydrogen we also support innovation in carbon capture, a key enabler for low carbon hydrogen.”
Greenhouse gas levels reach record high
Greenhouse gas levels have reached new record highs, prompting experts to warn “the window of opportunity for action is almost closed” to tackle climate change.
Average concentrations of carbon dioxide hit new highs of 405.5 parts per million (ppm) in 2017, up from 403.3 ppm in 2016 and 400.1 ppm in 2015, levels not seen for millions of years.
Levels of other key greenhouse gases methane and nitrous oxide in the atmosphere also rose, the World Meteorological Organisation (WMO) said.
In its annual bulletin on greenhouse gas levels, the WMO also warned of a resurgence in a potent greenhouse gas and ozone-depleting substance known as CFC-11.
There is no sign of a reversal in the trend in increasing greenhouse gas levels, which is driving climate change, sea level rises and more extreme weather and making oceans more acidic, the UN experts warned.
WMO secretary-general Petteri Taalas: “The science is clear. Without rapid cuts in carbon dioxide and other greenhouse gases, climate change will have increasingly destructive and irreversible impacts on life on Earth.
“The window of opportunity for action is almost closed.
“The last time the Earth experienced a comparable concentration of carbon dioxide was 3-5 million years ago, when the temperature was 2-3C warmer and sea level was 10-20 metres higher than now.”
The latest findings come after a report from the UN’s Intergovernmental Panel on Climate Change (IPCC) found net emissions of carbon dioxide must reach zero by around 2050 to keep temperature rises to 1.5C above pre-industrial levels and reduce the risks of climate change.
Professor Corinne Le Quere, director of the Tyndall Centre for Climate Change Research at the University of East Anglia, said she was “not surprised but I am very concerned” that the major greenhouse gases are rising unabated.
“It seems the urgency and extent of the actions needed to address climate change have not sunk in.
“Low-carbon technologies like wind, solar, and electric transport need to become mainstream, with old-fashion polluting fossils pushed out rapidly,” she said.