The Future of all Electric Schools - Peter Hazzard & Paul Giles, Cundall
Electrical demands in schools are unfortunately misunderstood. Industry guidance from CIBSE and BSRIA are extremely out of date, and this leads to overdesign and ultimately higher costs for the schools. Schools are already using far less energy than they were 10-15 years ago, and diversified loads are far lower in practice than we design for. We need to find a solution that reflects the current needs whilst keeping in mind net zero carbon.
On top of these existing issues, we are now seeing new ones. In recent years the need to include all electric heat pump solutions for new net zero carbon schools has become vital. We have to account for electric hot water systems (HWS), electric cooking, more electrical vehicle charging points, and potentially electric Bunsen burners. All of this compounds the over-sizing issues as diversities on these loads are poorly understood.
Unfortunately, few engineers check the maximum demand on a completed school, but we are finding that this is essential to identify changes and how we should be designing electrical supplies.
Since net zero carbon in operation (NZCiO) schools are so new, none have been in operation for over a year yet. We can however, use empirical data from existing schemes to understand peaks and troughs in load.
Most net zero carbon schools will have roofs full of photovoltaics (PV), and whilst you can’t rely on these to top up the incoming supply (there could be snow on the panels in winter) they can offer an opportunity to assist with smoothing demand. Battery storage solutions working with the PV and other demand control and energy storage techniques can assist to smooth out peaks in demand surrounding lunchtimes and other peaks in the day.