Switch to electric/hybrid boilers in buildings

Energy use in buildings contributes around 27% of global CO2 emissions in 2022, producing approx. 9.9 giga tonnes of CO2 emissions per year in both residential and non-residential buildings (direct and indirect emissions included). The space and water heating industry (residential and commercial buildings) accounts for 6.9% of emissions, producing approximately 2.5Gt of CO2 emissions per year (1). The remaining 20% of CO2 emissions are indirect emissions from the production of electricity and heat used in buildings (at 7.4 GtCO2e/year) (2).

In 2022, operational CO2 emissions from use, maintenance and managing (e.g. HVAC and electrical systems) of residential and non-residential buildings account for 9.9 Gt CO2e/year. Renewable heat and electricity generation can help to reduce the emissions associated with the electrification of space and water heating (2).

Electric boilers operate by use of electricity only for the heating of hot water. Meanwhile, hybrid boilers are a combination of renewable heat sources (e.g. air source heat pump) and traditional heating sources (e.g. natural gas or coal) to heat water.

Electric boilers provide high energy efficiency (99%). The main advantages of electric or hybrid boilers are a reduced carbon footprint, quieter operation and increased safety. Potential disadvantages are increased operating costs (due to electricity prices) and susceptibility to power outages. Typical market solutions allow for further integration with a solar photovoltaics system. This can lower cost throughout the use phase and allow for zero emission energy generation.

Higher hot water demand and lower efficiency rates make electric boilers less suitable for large households or buildings. Hybrid or dual energy boilers could enable cost efficient water heating in applications with higher hot water energy demands, while at the same time allowing for switching between energy sources based on current local electricity and gas prices (3).

In 2022, electric and hybrid boilers are used in multiple industries, e.g. agricultural soil steaming, petrochemical steam generation for reforming and cracking and food-related applications requiring hot water usage. Due to their high energy efficiency, ease of maintenance and installation and increased safety, the electrification of industrial processes is progressing. It is expected to achieve a wider range of applications within the next decade to other industries and reach high temperature heat possibilities.

Direct investment in the purchase and operation is a common implementation option typically considered by companies aiming to adopt electric or hybrid boilers.

Image: Fuel consumption for energy

Source: McKinsey. Plugging in: What electrification can do for industry

Climate impact

Targeted emissions sources

Installing electric or hybrid boilers for building heating reduces carbon dioxide emissions across all stages of the product life cycle and all GHG scopes.

• Category 1 (Purchased goods and services)

• Category 3 (Fuel- and energy-related activities not included in Scope 1 or Scope 2)

• Category 11 (Use of sold products)

• Category 12 (End-of-life treatment of sold products)

Decarbonization impact

Decarbonization impact across 3 phases:

• Manufacturing carbon dioxide emissions for electric boilers in most solutions should lead to overall CO2e decrease per single product, as their construction requires fewer components and moving parts than gas- or coal-based water heating solutions

• Use-phase of electric or hybrid boilers in buildings for heating purposes can have both negative or positive impact on carbon dioxide emissions, based on the local energy mix and share of renewables available. When paired with solar photovoltaic installation solution, it can enable nearly zero-emission water heating within buildings

• End-of-life treatment carbon dioxide emissions are equivalent to component recyclability is similar to gas- or coal-based boiler solutions

Business impact

Business benefits

Lower installation cost, possibility of lower operating cost, low operating noise, possibility of local tax breaks/subsides and higher solution efficiency.

Costs

• Impact on operating costs

Operational cost through use of electric/hybrid boilers is dependent on available price of electricity, impact on cost can be both negative (high electricity prices) and positive (solar photovoltaic panels integration).

• Investment required

Investment cost into electric or hybrid boilers depends on solution required in building infrastructure. Both positive and negative impact on investment cost should be expected. For electric only boilers, the investment cost should be significantly lower compared to other options due to the lack of moving parts and fewer components used during manufacturing. When considering hybrid or dual energy systems, the investment cost is expected to be substantially higher due to operating and control system complexities.

• Eventual subsidies used

Regional and country-specific subsidies should be researched.

Indicative abatement cost

The abatement cost for electric or hybrid boilers in buildings (dependent on technology currently in place):

• 70 to 140 USD/tCO2e (2022)

Impact beyond climate and business

Co-benefits

Local air quality improvements, possibility of carbon dioxide emissions reduction, improved local quality of air (health benefits in large cities).

Potential side-effects

Possibility of increased indirect carbon dioxide emissions.

Typical business profile

All individual and institutional clients in most industries and sectors interested in electric or hybrid boilers installation within their buildings and industrial processes for water heating or steam generation purposes.

Approach

The implementation of electric/hybrid boilers should be reviewed on a case-by-case basis, as insulation levels, building heating needs and local heating requirements may differ. Additionally, based on the industrial processes temperatures required, different solutions should be adopted to meet critical process efficiency and cost. Contact local specialists and service providers for relevant advice.

Stakeholders involved

• Company functions: All functions

• Main providers: Top boiler manufacturers by revenue – Mitsui & Co Ltd, Siemens AG, Mitsubishi Heavy Industries Ltd, Siemens Energy AG, ABB Ltd,

• Other: property users and energy source/electricity providers.

Key parameters to consider

• Solution maturity: recognized, available across all world regions widely and in steady development

• Lifetime: 15-25 years

• Technical constraints or pre-requisites: initial cost of installation, case solution viability must be assessed

• Additional specificities (e.g., geographical, sector or regulation): current building’s heating system efficiency and local energy source/electricity prices

• Eventual subsidies available: local subsidies and tax breaks must be reviewed

Implementation and operations tips

The implementation of electric or hybrid boiler must be assessed for specific adoption case, based on local energy and electricity prices, local energy mix carbon dioxide emission intensity, synergies with other solutions (e.g., solar photovoltaic panels). Additionally, the cost of maintenance/operation should be recognized.

Widespread scaling of electric or hybrid boilers is dependent on available local electricity prices, while the decarbonization potential is reliant on the available electricity mix emission intensity or renewable electricity sources.