If you’re looking to buy a new gas boiler for your home, it’s important to consider the environmental impact of your choice. Nitrogen oxides (NOx) are a harmful pollutant emitted by gas boilers during combustion, and they can contribute to poor air quality and respiratory problems. In the UK, there are regulations in place to limit the amount of NOx that gas boilers can emit. Here’s what you need to know.
Regulations for NOx emissions from gas boilers
The Energy-related Products (ErP) Directive is the main legislation governing the energy efficiency and environmental impact of heating and hot water products, including gas boilers. Under the ErP Directive, all new gas boilers must meet specific minimum energy efficiency and emission standards. Specifically, gas boilers must comply with the NOx emission limits set out in the ErP Directive, which are expressed in milligrams of nitrogen oxide per kilowatt-hour (mg/kWh) of heat output. The exact limit for a gas boiler depends on its rated heat output, with smaller boilers having a lower limit than larger boilers.
As of September 2018, the maximum NOx emission limit for gas boilers in the UK is 56 mg/kWh. This means that any new gas boiler sold in the UK must meet this limit or be more efficient. It’s worth noting that this limit applies to gas boilers only. Oil-fired boilers have a higher NOx emission limit of 120 mg/kWh.
Why are low NOx boilers important?
NOx emissions from gas boilers can contribute to poor air quality and health problems, particularly in urban areas where pollution is more concentrated. Reducing NOx emissions from gas boilers is an important part of the UK’s strategy to improve air quality and reduce harmful emissions.
Low NOx boilers are designed to emit fewer pollutants during combustion, helping to reduce the overall environmental impact of heating and hot water systems. By choosing a low NOx boiler, you can help to reduce your household’s contribution to air pollution and protect your health and the environment.
Local NOx emission limits in London
In addition to the national limits set out in the ErP Directive, London has its own local NOx emission limit for gas boilers. Due to the high levels of air pollution in the city, new planning applications for buildings in London are required to meet a lower NOx emission limit of 40 mg/kWh.
This local requirement is part of the London Plan, which sets out the Mayor of London’s vision and policies for the development of the city. The Air Quality Neutral policy within the London Plan aims to ensure that new development does not contribute to poor air quality, and the lower NOx emission limit for gas boilers is one of the measures taken to achieve this.
It’s important to note that the 40 mg/kWh limit applies to new planning applications only and not to existing boilers. However, choosing a low NOx boiler that meets this limit can help to reduce the environmental impact of your home’s heating and hot water system.
In conclusion, if you’re in the market for a new gas boiler, it’s important to choose a model that meets the NOx emission limits set out in the ErP Directive. Look for boilers that are labelled as low NOx, and consider their efficiency and environmental impact when making your decision. By choosing a low NOx boiler, you can help to protect your health and the environment, while also complying with national and local regulations.
Low NOx boilers for BREEAM
BREEAM (Building Research Establishment Environmental Assessment Method) is a widely recognized sustainability assessment method for buildings. One of the criteria for achieving credits in BREEAM is to ensure that the building’s heating system is energy-efficient and has low environmental impact.
In terms of low NOx boilers, BREEAM requires that gas boilers installed in buildings must meet specific NOx emission standards. In high pollution areas, where air quality is a concern, gas boilers are required to have a maximum NOx emissions level of 27mg/kWh to achieve one credit, and 24mg/kWh to achieve two credits. These NOx emission levels are significantly lower than the minimum required by the UK Building Regulations.
Examples of Low NOx boilers
There are a variety of companies that offer low NOx boilers in the UK, including:
- Worcester Bosch: Worcester Bosch is a well-known manufacturer of gas boilers and offers a range of low NOx boilers that meet the requirements of the Ecodesign Directive. Their Greenstar i range of boilers, for example, emit just 23mg/kWh of NOx.
- Vaillant: Vaillant is another major manufacturer of gas boilers in the UK and offers a range of low NOx boilers, including the ecoTEC pro and ecoFIT pure ranges. These boilers emit less than 36mg/kWh of NOx and are compliant with the Ecodesign Directive.
- Baxi: Baxi is a UK-based manufacturer of boilers that offers a range of low NOx options, including the Baxi 600v and Baxi 800 series. These boilers emit less than 40mg/kWh of NOx and are also compliant with the Ecodesign Directive.
- Ideal Boilers: Ideal Boilers is a British company that offers a range of low NOx boilers.
It’s important to note that these are just a few examples of the many providers of low NOx boilers in the UK. The above information was correct at the time of writing but it essential that you do your own research and inspect the technical specification sheet to make sure the product specifics have not changed and meet any local requirements, before making a purchase. Greenavon does not take any commission from these purchases.
What are the alternatives to Low NOx boilers?
While low NOx boilers are an effective way to reduce the environmental impact of heating and hot water systems, there are other alternatives available that may be suitable for some households.
One alternative to gas boilers is heat pumps. Heat pumps work by extracting heat from the air or ground outside your home and using it to heat your home and water. Heat pumps are a renewable technology and can be more efficient than gas boilers, resulting in lower greenhouse gas emissions. However, they can be more expensive to install and may not be suitable for all properties.
Another alternative is connecting to a low-carbon power network. If your home is connected to a power network that uses renewable energy sources, such as wind or solar power, then your heating and hot water will have a much lower environmental impact than using a gas boiler. However, this option is only available in certain areas and may require significant infrastructure changes.
While these alternatives have their benefits, they also have drawbacks. Heat pumps can be noisy, particularly if they are not installed correctly, and may not be suitable for all households. Connecting to a low-carbon power network can also be expensive and may require significant infrastructure changes.
Ultimately, the choice of heating system will depend on the specific needs and circumstances of each household. It’s important to weigh the pros and cons of each option and consider factors such as efficiency, environmental impact, cost, and suitability for your home.
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