Blog

Why Your Site May Not Be Ready for EV Charging

The benefits to a business of installing EV charging, both for their vehicle fleet and commuting staff, are increasingly clear. 

After a hefty upfront investment, on-site charging helps to unlock lower running and repair costs for vehicles and the ability to operate an EV fleet far more efficiently. Implemented properly as part of a wider sustainability strategy, EV charging also has the potential to transform your carbon emissions performance. When combined with on-site green generation or other sources of green energy, EV charging sees one of the largest sources of emissions for many businesses, their vehicle fleet, become one that runs primarily, or even entirely, on clean energy. 

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. 

The installation of a Battery Energy Storage System (BESS) is able to solve this issue of balancing on-site generation and demand. This technology allows on-site generation to be stored when generation conditions are high, such as during sunny periods. This power can then be tapped into when needed to provide the additional power needed to charge electric vehicles. 

Similarly, if on-site generation is not a consideration, a BESS can still help you avoid exceeding your maximum power capacity and move forward with your EV charging plans. Power could be stored at times of low demand, such as overnight or at weekends when operations may not be running, and used to charge your EV fleet during normal business hours. This intelligent management of your on-site power flows will avoid the need to upgrade your maximum capacity or purchase a new grid connection. 

How to Prove the Solution to Gain DNO Approval 

An important additional capability to help gain approval for EV charging infrastructure is the use of accurate digital modelling of a system. This can virtually model and simulate your site’s power flows to demonstrate to your DNO that the technology will operate as intended, without suddenly placing an additional, unexpected strain on your local infrastructure. It also provides you with the confidence that a significant investment in power infrastructure is going to provide the functionality you are looking for. 

Properly implemented, BESS can unlock high-speed EV charging while protecting the entire site from the risk of disruption as DNOs continue to struggle to balance distribution networks.