Nuclear has clear benefits in terms of net zero electricity options. But when it comes down to the tough nut of low-carbon heating, it’s a hands down winner.

Almost half of all energy demand for use in buildings goes on space and water heating and, according to the IEA, that led to around 2450 million tonnes of direct CO2 emissions in 2021. Fossil fuels still meet over 60% of the requirement for heating and it is widely considered one of the harder nuts to crack in terms of a low-carbon alternative.

Worldwide, natural gas is still the most common fuel used for heating globally. IEA figures indicate it alone accounts for around 40% of heating energy demand and in some countries, such as the USA, this figure is as high as 60%.

A year into the conflict in Ukraine though, and times have definitely changed. Russian gas is now off the table and the associated price volatility and security of supply risks for the heating sector have injected a new urgency into seeking out alternatives. Even beyond the conflict, the carbon crisis demands substantial action to reduce the carbon impact of such a large source of emissions if we are to meet our Net Zero ambitions.

There are signs of improvement here as the role of alternatives emerge, albeit slowly. And, per unit area heating CO2 intensity has fallen – by almost 40% between 2000 and 2021 – largely as a result of improved energy efficiency of both building stock and boilers.

District heating and combined heat and power are well known approaches that can improve energy efficiency and reduce the carbon impact of space and water heating. However, while far more prevalent in continental Europe and Asia, especially China, their uptake has been decidedly muted in some regions. That must change but there also needs to be a rethink when it comes to fuelling district heating networks.

China is taking a lead here by developing nuclear powered heating networks. The country’s largest nuclear heating network to date, Warm-U-Clear-1, was commissioned last November. Developed by the State Power Investment Corporation (SPIC), the project brings nuclear warmth to some 200,000 people living in Haiyang, which has been declared the nation’s first ‘zero-carbon’ heating city.

Phase 1 of this project was initiated in 2019 with just over 31 MW and named as the National Nuclear Heating Commercial Demonstration Project by the National Energy Administration. At more than 200 MW Phase II followed in 2021 and the 900 MW phase III is now underway with construction of the heating network now begun and commissioning due at the end of the year. Eventually, SPIC plans to extend the heating area to the entire Jiaodong peninsula of Shandong Province. According to SPIC statistics, over the three heating seasons that have occurred since the Warm- U-Clear-1 Project started, the nuclear heating approach has already avoided some 420,000 tonnes of direct CO2 emissions.

It’s true that the use of nuclear power for district heating is still in its infancy but it is equally evident that there is a significant opportunity for nuclear power to make a major contribution to decarbonising a huge source of emissions.

Europe currently leads the world on clean energy integration in district heating, with about 25% of district heat supplied from renewable sources. This effort is led by countries like Sweden and Lithuania. However, both Sweden and Lithuania also have a civil nuclear power programme. The implications are clear. Significantly faster rates of low-carbon heat network deployment are needed to get the world on track to meet Net Zero emissions targets by 2050. At the same time, valid concern over security of energy supplies are driving renewed interest in nuclear capacity. Given that the world must exploit every opportunity to reduce its carbon emissions there is an obvious answer. The rest of the world just needs warm to the idea of nuclear heating.

By David Appleyard, Editor, Nuclear Engineering International