However, one factor you may not have considered in the planning for your new EV charging installation risks the entire project being blocked. Many business sites already operate at close to their maximum authorised capacity during periods of peak demand. This means that the addition of EV charging, particularly rapid charging, risks exceeding the amount of power your Distribution Network Operator (DNO) has authorised for your site.
Why Your DNO Might Block Your EV Charging Plans
DNOs are responsible for the management, maintenance, and upgrades of your distribution network, the local electricity infrastructure that distributes power from the high-voltage transmission network (The National Grid) to end users. The UK’s energy grid was designed during a period when power was centrally generated, before being dispatched to end users. Today, DNOs face the difficult task of balancing demand with distributed generation from a wide range of micro-generation feeding back into the grid. This can put a lot of strain on localised power infrastructure, risking exceeding the safe capacity of equipment such as transformers.
If your DNO feels that your proposed project risks putting additional pressure on an already stretched distribution network, they are likely to turn down your application outright. In the case of EV charging this will typically be when your demand would exceed your authorised capacity, but similar issues can arise for on-site generation that may feed more power back into the grid than it can safely tolerate.
How to Solve the Problem
One obvious option when an application is turned down might seem to simply increase your authorised capacity. However, in practice this is impractical for most organisations. Additional capacity may require a new grid connection to allow higher levels of power to safely reach your site. Costs differ by region, but easily run into six or even seven figures. Even if that is a cost your business can absorb, your DNO may still turn down an application if the new connection would put additional stress on your distribution network.
Another solution you may consider is to install on-site generation to provide the additional power, rather than sourcing it from the grid. While a much more practical solution, alone it is still unlikely to placate a nervous DNO. The question remains what happens with excess power generated from solar, for example, when no vehicles are being charged. Similarly, what happens when vehicles need to be charged overnight, when solar is not generating? Both scenarios continue to risk putting additional pressure on your local infrastructure.