Why electric vehicles are driving us towards demand management
By Simon Anderson, Chief Strategy Officer, geo — Without wishing to be dramatic, if something is not done about the demands on the national grid, we are literally in danger of the lights going out. We’re all aware that demands on electricity surge during commercial breaks, or during the cooking of the Christmas lunch, but what happens if demand outstrips supply on a much longer basis?
This issue is a concern at the local network level where the growing electrification of heating and vehicles is beginning to be felt more strongly. Electric cars are becoming more popular, indeed most major manufacturers have already launched, or are in the process of developing electric models and new housing developments are adding electric charging as standard. What may not be realised is that the power required to charge just one vehicle is equivalent to the electricity used in an entire day in an average home. The concern is that local electricity networks have not been designed for this increase in demand: substations have limited bandwidth, particularly established ones.
One solution is ‘demand management’, where electricity utilities use different methods and mediums to modify demands for energy through price signals and actively managing appliances. This is a concept currently used almost exclusively for commercial and industrial users, but given that they make up only 20% of peak electricity demand, whilst domestic consumption accounts for 50% and small business consumption for 30%, it seems more than relevant to extend it to home owners and SME consumers in the UK today.
But how do we do that?
Consider the principle on which storage heaters are based; they are charged during the night when electricity demand is at its absolute lowest and the energy is stored until it is needed. With the right technology in place, the same could be done in homes.
Could we repeat the exercise with electric cars? Possibly. Network Operators are already contemplating how they could control the times at which a car could be charged from the grid. The homeowner would be made aware that if they plugged the car in at 7pm, it may not start charging until much later when demand is lower. However, for this to work, infrastructure needs to be in place to support communication from the car to the home to the grid. But possibly of greater importance is the question: is this the sort of restriction we would be happy with? Would it be flexible enough to let us use our cars when we want or need to, especially if we don’t operate by the standard 9 to 5?
The Hybrid Home
How about if modern homes were like a hybrid car and fitted with energy storage and a management system was installed to control it? This would allow energy to be stored when prices are low and to be used when prices are high. As the system is permanently connected to the grid it would level out demand, including from electric vehicles, and ensure that the current local network could support the increased demands without being strengthened. In addition, the system would store locally generated electricity, increasing home consumption (currently, on average, over 50% is exported) doubling the value of home solar installations and enabling the expansion of solar.
And this is possible now: we are at the start of the smart meter roll-out, solar panels are currently installed on close to a million residential roofs in the UK and energy storage technology is available. This type of initiative will also provide the means to sell electricity back to the local grid through an aggregator. Not only will this allow consumers to earn money from their energy resources and reduce their bills, they will also be providing a valuable commodity to the grid.
By implementing Hybrid Homes, demand for electricity will be smoothed out and peaks in consumption will be reduced, lessening the pressure on the grid. According to Imperial College and Cambridge University*, as much as £8bn a year of additional investment in grid infrastructure, the cables, pylons and transformers that deliver power around the country could be avoided by 2030 if demand for electricity is smoothed across the day.
* "Delivering Future Proof Energy Infrastructure," February 2016