The Need for Heating and Decarbonisation Strategies for Buildings

Introduction to Building Emissions and Heating

Buildings account for a significant share of global energy use and carbon emissions. According to the International Energy Agency (IEA), the building sector accounts for nearly 30% of global energy consumption and 27% of energy-related CO₂ emissions. A large portion of these emissions stems from the need for heating, especially in colder climates, where space heating and water heating are essential for comfort and functionality.

Decarbonising the heating systems in buildings is important to meet global climate targets, improve energy efficiency, and reduce overall carbon footprints.

Challenges of Heating Systems in Buildings

Conventional heating systems rely heavily on fossil fuels such as natural gas, oil, or coal. These fuels are not only carbon-intensive but also contribute to local air pollution. Some key challenges include:

Fossil Fuel Dependence: Traditional boilers and furnaces burn natural gas or oil, which emits large amounts of CO₂.

Inefficiency: Older heating systems often have low efficiency, meaning more energy is used to produce the same amount of heat, leading to unnecessary emissions.

Retrofitting Costs: Many existing buildings are not designed to accommodate newer, more efficient heating technologies, making retrofits expensive and logistically challenging.

Seasonal Demand: The demand for heating is highly seasonal, peaking in colder months, which places strain on energy systems and increases reliance on high-carbon energy sources like coal or oil-fired plants.

Key Decarbonisation Strategies for Heating in Buildings

Energy Efficiency Improvements

• Insulation: One of the most effective ways to reduce the need for heating is by improving building insulation, including walls, roofs, and windows. Better-insulated buildings retain heat longer, reducing the amount of energy required for heating.
• Energy-Efficient Windows: Double or triple-glazed windows significantly reduce heat loss.
• Smart Thermostats: These systems can optimise heating by adjusting based on real-time occupancy and weather conditions, thus reducing unnecessary heating.
• Heat Pumps: Air Source Heat Pumps (ASHPs): These extract heat from the outside air and are significantly more efficient than traditional fossil fuel heating systems. Even in cold temperatures, ASHPs can provide efficient heating.
• Ground Source Heat Pumps (GSHPs): These use the earth’s stable underground temperature to provide heating and are incredibly efficient, though they require more upfront investment.
• Heat Pump Efficiency: Heat pumps can be three to four times more efficient than gas boilers, significantly reducing the energy required for heating.

Electrification of Heat

• Electric Boilers: While not as efficient as heat pumps, electric boilers can be powered by renewable energy sources like solar or wind, drastically reducing emissions.
• Integration with Renewable Energy: When heating systems are powered by renewable electricity, the overall carbon footprint of the building decreases significantly. Electrification also helps align heating systems with decarbonisation pathways as the grid becomes greener over time.

District Heating

• District Heating Systems: In urban areas, district heating can be an effective solution. These systems centralise heat production, which can be generated from renewable sources such as biomass, geothermal energy, or waste heat recovery.
• Low-Carbon Fuel Sources: District heating systems can transition from fossil fuels to renewable energy sources like solar thermal or biomass, providing a decarbonised solution for multiple buildings at once.

Hydrogen as a Future Fuel

Green Hydrogen: Hydrogen produced using renewable energy can potentially replace natural gas in heating systems, particularly in areas where electrification is difficult. However, the technology and infrastructure for widespread hydrogen use are still in development.

Hydrogen Boilers: These are under testing for residential and commercial use and could be a viable decarbonisation pathway in the coming decades.

Policy and Financial Considerations

Government Incentives: Many governments offer financial incentives for building owners to upgrade heating systems, such as grants, tax rebates, or low-interest loans. These policies encourage early adoption of decarbonised heating technologies.

Building Codes and Standards: Stricter building codes that mandate energy efficiency and low-emission heating solutions can accelerate the transition to decarbonised heating systems.

Carbon Pricing: Imposing a carbon tax on fossil fuel use in heating could make low-carbon heating technologies more economically competitive, driving market adoption.

The journey to Net Zero buildings starts with better energy performance. Increased awareness of energy use and the need for greater efficiency is the first stepping stone to enable consumer decisions to improve building energy performance and use smarter, more efficient products and systems. 

To meet Net Zero virtually all heat in buildings must be decarbonised. The benefits of more efficient, low-carbon buildings for consumers are clear: smarter, better-performing buildings, reduced energy bills and healthier, more comfortable environments. Additionally, studies indicate that more energy-efficient properties typically have a higher value than less efficient ones.

Decarbonising heating systems in buildings is a critical step in achieving climate targets. Combining energy efficiency measures, electrification of heating, heat pumps, district heating, and future technologies like hydrogen offers a viable pathway to reduce emissions. Policymakers, building owners, and industry players must collaborate to accelerate this transition by providing financial incentives, revising building regulations, and investing in innovative technologies.