Electric cars could help supply millions of households with electricity in the coming years simply by using their batteries. The electricity in the vehicle battery could be fed back into the grid instead of being stored. The technique was developed in Japan and our research will help understand how best to use it in the UK.
Many Electric Vehicles (EVs) are made with the ability to use their on-board battery to return power to the power supply to which they are connected. Whether it’s the owner’s home or the power grid in general, these technologies have been used primarily by governments and electric car manufacturers to balance demand on the power transmission grid or grid.
The ability to use these giant connected batteries is in line with managing and delivering cleaner grids in the future – instead of burning fossil fuels to generate electricity, we should use clean renewable energy sources such as wind and sun when they are available and store the electricity in batteries, unless. So by charging electric vehicles from renewable sources, we can reduce our greenhouse gas emissions.
The plan sounds great, but it will be tricky because electricity is difficult to store. But we already store huge amounts of electricity – in our cars. With around 1% of the 27 million UK households currently owning an EV with an average 60 kWh battery each, those 300,000 EVs could store a whopping 18 GWh of electricity that could be meaningfully used to power homes. That is more than the Dinorwig pumped storage plant in Snowdonia, Great Britain’s largest storage facility, which stores around 9 GWh.
Dinorwig Power Plant, known locally as Electric Mountain or Mynydd Gwefru, is a pumped storage power plant.
Phil Woolley / Shutterstock.com
By 2030, the UK could have almost 11 million electric vehicles on the roads. Assuming that 50% of these vehicles could feed unused energy back into the grid, this would open up the possibility of supplying 5.5 million households with electricity.
How do we make it happen?
For cars to be able to technically supply the grid with electricity, three things have to happen. First of all, a reciprocal energy transfer from the car to the charging point should be enabled. This system is known as Vehicle-to-Grid and was first introduced in Japan after the Fukushima disaster and the subsequent blackout.
However, more areas of development are needed to introduce the technology. This includes installing vehicle-to-network charging hardware at home, vehicle compatibility and changes in the energy market. There are also two competing types of fast chargers that need to be addressed, possibly with devices that have both types of connectors.
On March 11, 2011, a 9.0 magnitude earthquake and subsequent tsunami devastated northeastern Japan and triggered a nuclear disaster at the Fukushima Daiichi nuclear power plant.
Santiago Hernández Lloret / Alamy
The third part of the technical puzzle is the support provided by the power distribution networks. Some parts of the network are unable to return a significant amount of power through the connections at the same time, so local networks must ensure that they can handle it.
Involve drivers
How do we make sure people get involved in the program once the technology is fully installed? We are researching consumer acceptance and knowledge of vehicle-to-grid systems to show drivers how the technology works and to prevent their batteries from running out of power when needed.
Currently, most of the trials are being done by energy companies or power distribution companies trying to find out how the technology works commercially and can balance the power grid. But we believe that the focus should also be on cost benefits, eco-certification and driver comfort.
Charging EVs with the cheapest energy and selling energy back to the grid at peak times could allow customers to earn up to £ 725 a year. This is on top of the fuel cost savings: an electric vehicle costs an average of £ 500 per year compared to £ 1,435 per year for a petrol or diesel.
Reducing your environmental footprint, saving fuel costs, and running your home on cheaper, clean energy are all great benefits, but low car battery cases can unsettle many angry owners.
Other concerns include: the potential cost of installing compatible V2G chargers at home; Lifestyle impact and inconvenience of delayed charging of electric vehicles (when the car is providing power to the house); and the fear of battery degradation (which some research suggests is warranted but is outweighed by the potential benefits).
UK electricity and gas regulator Ofgem plans to invest millions of pounds in creating a more flexible energy system to support vehicle electrification and renewable energy generation, and to make the transition to a low carbon economy fairer and affordable.
If enough motorists took advantage of vehicle-to-grid technology, the UK could gain the power generation capacity of up to ten large nuclear power plants and reinvest the saved costs in developing clean energy and flexible energy systems.
The process won’t be smooth. The solutions are numerous, but they require the assistance of utility companies and even automakers and finance companies. There are many pieces of the puzzle to solve, but with the average car idle 95% of the time, the chances that its power source could be used for greener, cheaper living are enormous.
