hese are uncertain times for the people of Britain as the nation negotiates its departure from the European Union. One thing, however, is clear – all EU legislation will continue to apply in the UK until after Brexit, which is formally set for March 2019. So it is worth noting the impending mandatory EU requirements relating to nitrogen oxide (NOx) emissions from space heaters that will be imposed from next year.
The Ecodesign of the Energy-related Products Directive (ErP) will enforce maximum NOx emissions of 56mg/kWh for gas and liquefied petroleum gas (LPG) boilers and 120mg/kWh for oil-fired boilers. The legislation, which applies to new equipment up to, and including, 400kW on both new-build and replacement projects, will come into effect from 26th September 2018.
It follows tighter ErP energy efficiency requirements for space heating introduced in September 2015. The aim is to ensure that only the most energy-efficient, low NOx heating products are manufactured, specified and installed across the UK and Europe.
Clearly, any legislation that tackles energy costs and emissions reduction is to be welcomed. In refurbishment projects the EU predicts a 20% drop in energy bills where older equipment is replaced with ErP-compliant products. The reduced greenhouse gas emissions will also help the UK meet its 80% emissions reduction target by 2050.
Mind the NOx
But why the focus on NOx? NOx has come under scrutiny of late as clean air warnings have been issued across a number of UK cities. According to the Department of Environment, Food and Rural Affairs (Defra), most UK cities and towns reached ‘high’ or ‘very high’ levels of pollution at some point last year. Poor air quality has been linked to asthma and lung and heart-related conditions. Defra measures levels of five pollutants: ozone, nitrogen dioxide, sulphur dioxide, and PM2.5 as well as PM10 particulate matter. Of these, it claims that NOx alone is responsible for the premature death of 23,500 citizens each year in the UK.
While road traffic has been identified as a major contributor to outdoor pollution, non-domestic buildings also typically emit NOx. According to statistics from the City of London Corporation, 38% of NOx emissions in the Square Mile come from gas for heating buildings.
The introduction of maximum NOx emissions from heating is therefore an important step towards achieving cleaner, less polluted air.
Promoting low NOx heating
Of course, designing for low NOx heating is not a new concept. The London Plan, for example, already recommends the use of low NOx boilers within borough council and City of London buildings.
Then there’s BREEAM, the environmental assessment scheme, which has certified and rated the sustainability of buildings since 1990. Its Pol 2 emissions category aims “to encourage the supply of heat from a system that minimises NOx emissions, and therefore reduces pollution of the local environment”. It awards a maximum of three credits for a heating plant with a dry NOx emission level of up to or less than 40mg/kWh. These low NOx credits are added to the results from the other categories, ranging from energy to ecology, to provide a final building rating.
From a commercial perspective, higher BREEAM accreditation brings economic and environmental advantages as these buildings tend to generate environments that are more comfortable and more sustainable to operate.
While the crackdown on NOx does place more stringent demands on new and replacement boilers, forward-thinking manufacturers are ahead of the game. In fact, for some manufacturers, reducing emissions has been a priority for years with the result that many low NOx condensing boilers are now in their third or fourth generation. Advanced models, like Remeha’s comprehensive Quinta range, have been engineered from the outset to achieve maximum high efficiencies and low NOx criteria.
With high gross efficiencies of up to 98% and ultra-low NOx emissions at or below 40mg/kWh, they meet the EU standard EN 15502 Part 1 2015 Class 6 for NOx. This makes them eligible for maximum BREEAM credits and future-proof to the ErP 2018 requirements. Crucially, they are also certified for operation on liquefied petroleum gas (LPG), making them a flexible, viable solution for off-grid projects.
The next steps
So what are the implications for specifiers? On new-build and refurbishment projects alike, the focus should be on ensuring that only ErP-certified. high-efficiency low NOx heating products are specified.
In older buildings, consider replacing any ageing or inefficient equipment with the latest ultra-low NOx condensing boilers. Even when well maintained, a 25-year-old boiler will achieve 70% gross efficiency at best and comparatively high NOx emissions.
The tighter ErP regulations are effectively driving a move to condensing boilers. While switching to condensing boiler technology can and should be seamless, take time to plan ahead to ensure a smooth transition.
Size the heating load of the building accurately to meet its use. A well-sized boiler will help create a more comfortable, productive environment and improve the energy performance of the building. With existing buildings, take the opportunity to resize the load – the building and how it is used may have changed since the last boiler installation.
Good control is essential to optimise boiler and system performance, so ensure that effective controls are included at the design stage. This will keep heating efficiencies high and NOx emissions low.
Finally, take time to involve manufacturers at the outset when their specialist input is most valuable. Early engagement can ensure that the most appropriate equipment is specified and that the design is robust.
Addressing the energy performance of the built environment remains one of the greatest challenges facing the nation. ErP might just be the driver we need to tackle air pollution and energy waste. With the ready availability of cost-effective, ErP-compliant condensing boilers, backed by knowledgeable support from manufacturers, the tighter requirements are entirely achievable. And if the result is cleaner air to breathe, we’ll all be winners.