Local point-of-use electric water heaters and electric immersion cylinders have been widely specified for many years. More recently, electric combi-boilers have been promoted by industry and manufacturers’ as a potential greener alternative to the traditional gas-fired combi-boiler.
Utilising electricity as the energy source, instead of gas, has some obvious advantages including the omission of discharge flues and annual Gas Safe inspections, however there are several disadvantages which must also be considered by landlords and the professional team at the outset of a project.
Running Costs
Currently (and for the foreseeable future) electricity is more expensive than gas, therefore, running costs will be considerably higher. Manufacturers’ are quick to note that annual Gas Safe inspections are not required – but it is still highly recommended that electric combi-boilers are serviced annually to prolong economic lifetime and good operation.
Given that the initial outlay for an electric combi-boiler (in terms of the boiler itself) is typically greater, planned preventative maintenance is arguably even more essential, even if it is not a statutory requirement.
Power Supply Requirements
A typical electric combi-boiler sufficient to serve a two-bedroom two-bathroom apartment is likely to be in the order of 12 kW. This is a very large power supply for a residential dwelling and the electrical sub main distribution infrastructure will need to be sized accordingly. This can be more easily integrated on new build projects but may not be feasible to accommodate within an existing building.
The rating of the incoming power supply serving the building will also need to be assessed, along with the feasibility and cost implications of upgrade.
Power Cuts & The Network
Power cuts occur more frequently than gas network outages – it goes without saying that electric boilers will not function during a power cut (unless the building is afforded with a form of standby power generation)!
It is also important to consider the ever-increasing demand on local electricity networks as electric vehicle charging becomes more and more prevalent. It can no longer be assumed that increasing a buildings incoming power supply will be achievable without significant local infrastructure enhancement – and cost.
EPC Ratings
Minimum Energy Efficiency Standards (MEES) stipulate minimum EPC Ratings for landlords. These regulations came in to force on 1 April 2018 for new lets and tenancy renewals and have now extended to include all existing tenancies as of 1 April 2020.
EPC assessments favour gas. Ratings analysis is based on the unit cost of energy and as explained above, gas is currently cheaper than electric. Assessments also evaluate potential CO2 emissions and as electricity is produced through inefficient and outdated power stations, the final rating is further adversely affected.
Minimum EPC Ratings may still be achieved by landlords through other means such as secondary glazing, internal insulation, energy-efficient lighting etc. but an electric boiler will not contribute to achieving the lowest EPC Rating possible.
Summary
These considerations highlight the importance of undertaking a detailed feasibility study at the outset of a project in order to ascertain the benefits and drawbacks of gas versus electric.
As well as feasibility assessment on a project by project basis, the wider industry, power generation and utility companies needs to implement large scale investment and revolutionising as well as transforming statutory compliance requirements if electric boilers are going to be advocated as the ‘green’ boiler of choice in the future.