All new housing developments should be fitted with three-phase electricity supply to update them from the single phase norm that has been in place since before World War II, according to a new report out today.
The Renewable Energy Association (REA), joined by the UK’s largest distribution network operator (DNO) Western Power Distribution (WPD), has made the case that upgrading the electricity supply to homes would pave the way for greater adoption of solar, renewable heat and electric vehicle charging.
The current model in the UK is for housebuilders and network operators to connect each house to one of the three phases running down mains cabling. This allows for less power use in a typical home and limits how its load can be distributed.
The paper, “The feasibility, costs and benefits of three phase power supplies in new homes”, argues that this has been the norm since the post-war period and should now be updated to reflect the growing need for greater facilitation of distributed energy resources in UK homes.
Nina Skorupska CBE, chief executive of the REA, said: “The built environment is a major source of carbon emissions. If we are serious about delivering on our ambitions to reduce energy bills, meet our carbon targets, and deliver on our Industrial Strategy aims, we should ensure that they have adequate electrical connections.
“Three phase power supplies in new homes can facilitate a more rapid deployment of renewable heat systems, greater uptake in rooftop solar PV, and greater choice in charging your electric vehicle.”
WPD is currently trialling the use of three-phase connections at the Parc Eirin Energy Positive Homes development in Wales in order to determine the costs and benefits of doing so.
Both solar thermal and building integrated PV are used alongside battery and thermal storage, smart heating controls and appliances, and electric vehicle charging to ensure that the energy generated by each home is flexible and available for use.
WPD is investigating the best configuration for wiring in the home to allow diversification of load across each phase within it and across the development. It claims the additional cost for installation should eventually be marginal, although it is anticipated that an additional cost will be inevitable on earlier projects due to scarcity of three phase equipment and the new electrical design.
However Mark Dale, innovation and low carbon engineer at WPD, has said that the use of three phase connections in homes will be needed to help networks become more flexible in how they design and maintain their systems.
“With the connection of more and more distributed generation on our networks we need to become more flexible in the way we design and operate our networks. The current policy of installing single-phase supplies in new homes has been the norm since before the Second World War and should be reviewed,” he said.
“Three phase connections will allow for more solar PV and battery storage, and well as for faster home EV charging. It will give customers and network operators the flexibility required to match demand and generation as efficiently as possible by utilising smart meter tariffs whilst, at the same time, reducing network losses.”
The REA argues that current regulations governing DNOs constrain them from installing “marginally higher cost” three-phase connections, as they are compelled to carry out the lowest-cost solutions. However, Skorupska added that over time these costs would reduce with the government’s blessing.
“Additional costs to housebuilders are already low for a three-phase connection compared to a single-phase in new homes. If the government compelled the network operators to fit new homes in this way, the cost would fall even lower,” she said.
In response to the report, the Energy Networks Association – representing the transmission and distribution network operators for gas and electricity in the UK and Ireland, including WPD – agreed that three-phase connections would allow network operators to better manage high-levels of EV and heat pump uptake.
However, it has said that a discussion was required to establish who should meet the additional costs of adopting the more expensive practice of installing three phase connections.
“There is a cost attached to this, due to additional network reinforcement and increased customer connection costs. The DSO transition, behind-the-meter technologies, like storage, and the greater use of flexibility services are key to keeping that cost down, but there still needs to be an open and public discussion amongst policymakers about how it is paid for,” an ENA spokesperson told Current±.