Under new efficiency regulation Boiler Plus (introduced in 2018) it became mandatory to fit an ‘advanced energy saving measure’ with a new combi boiler and 'time and temperature' controls with boilers that work with a hot water cylinder.
Advanced energy saving measures include weather and load , which offer 3% and 4% efficiency uplifts respectively. However, the regulations were diluted by the inclusion of ‘automation and optimisation’ controls, many of which are essentially forms of ‘smart’ on/off control that add just 1% of efficiency (or 0% according to the 2016 SEDBUK consultation).
The regulations were further weakened by the incompatibility of many load and weather compensation controls with many boilers. Compensation controls must speak the same language as the boiler to achieve 3-4% efficiencies, otherwise they operate as an on/off control that fall into the 1% (maybe 0%) efficiency category. This is because some boiler brands prefer to restrict compatibility to their own controls for a multitude of reasons.
Consumers are also uninformed on the true efficiency of smart controls. If they do not speak the same language as the boiler they are little more efficient than a basic on/off control and as an industry we are long past such rudimentary measures.
The Future Homes Standard and meeting net zero by 2050
The Government’s Future Home Standard proposes a significant uplift in the energy efficiency standards for new build homes. By 2025, at the latest, it is proposed that no new homes are connected to the gas grid. An interim uplift in standards will come into force this year. (The proposed standard for existing homes is due out shortly.)
The interim standards make no proposed changes to boiler or system efficiency, only to move from the SEDBUK rating of 89.5% to ErP of 92% in line with standards for existing properties. But as we now know, this does not represent an uplift in efficiency.
Some mention is made of limiting system design temperatures to 55 degrees or lower, which would improve efficiencies, but nothing is stated on how this achieved.
The complete absence of a tightening of heating controls standards under Boiler Plus is an opportunity missed. Tangible efficiency improvements will only come with mandatory requirements to fit compensation controls that offer a 3-4% uplift and ensure universal compatibility.
Energy Performance Certificates (EPC)
Aside from raising questions over the usefulness of boiler efficiency labelling, consumers continue to be deceived by expected energy savings from new boilers. The current EPC guidance recommends that householders with non-condensing boilers should move to a condensing boiler, at a cost of £2,000-£3,000, in order to improve the energy efficiency banding of their homes.
Condensing boilers fitted from 2000 onwards had efficiencies of around 78%. As most new boilers are fitted with an on/off control (including smart controls when they do not speak the same language) then they are at risk of achieving a very small uplift in efficiency and a similarly small reduction in fuel bills.