HOUSING | SMART GRIDS GRID UNLOCKED If electric vehicles and batteries are to herald an all-electric future for homes, smart tech must be developed and tested to ensure there is always available energy to match household demand. Andy Pearson reports L ark Rise, the focus of this months CIBSE Journal case study, demonstrates that the building as a power station concept is possible. Equally importantly, Lark Rise by managing its peak electrical demand indicates that, if the concept were to be rolled out nationally, an electrical Grid powered by renewable energy is viable. It shows how the smart energy revolution has the potential to enable the UK to be fuelled entirely by renewable energy, says the buildings architect, JustinBere. A Grid powered by renewables has the potential to turn electricity pricing strategies on their head. Currently, gas, oil and coal power are a significant proportion of the UKs generating capacity. All these fossil fuels are commodities, traded on financial markets, with the cost of electricity based on the cost and quantity of fuel used in its generation. Wind and sun, however, are not tradable commodities; they do not cost anything, so users are effectively charged only for the use of the infrastructure, which will change the relationship householders have with their power supplier. The system we had 20 years ago was that demand was what it was, and NationalGrid turned things on and off to meet demand, said John Fox, practice manager, business model innovation, Energy Systems Catapult, at this years Futurebuild event. Renewables cannot be switched on and off; for that reason, we have to make demand follow supply and harvest energywhen renewables are providing, andtrytominimise energy use when that is not thecase. What this means in practice is that a householder who can be flexible with their electrical demand can have a significant impact on their carbon intensity and, potentially, the price they pay for power. Without battery storage, any impact is likely to be limited people may be happy to run their washing machine or dishwasher overnight or during the day, but how many will be prepared to move the time of their evening meal or turn off their television to avoid the evening peak? It is an evening peak that could be made worse by the rapid growth in electric vehicle sales, which could result in large peak-load increases. Currently, electric cars make up a relatively small proportion of all vehicles sold in the UK, but their numbers are growing rapidly as they become more affordable, battery technology improves andcities introduce clean air initiatives, such as Londons Ultra LowEmissions Zone, which came into force on 8 April. The expectation is that Building Regulations will require all new homes 28 May 2019 www.cibsejournal.com CIBSE May19 pp28-30 Electric homes.indd 28 26/04/2019 17:07