EVs on the grid – challenges and opportunities

Adam Pigott, engineering manager, Kinect Energy Group, discusses EV charging, its applications, challenges and opportunities for utilities.

While electric vehicles (EVs) currently account for a very small fraction of the cars on the road, sales are rising and that trend will only accelerate as prices fall and range increases. This will inevitably impact any business that has an employee or customer car park. Consequently organizations need to consider the impact of EV charging and future EV trends on their energy strategy. This is particularly the case for businesses who may need to install multiple charging or rapid charging infrastructure at their premises.Many businesses will be unaware that installing significant numbers of EV charging points is likely to have implications for their existing electricity supply, which may need upgrading to cope with the increased demand.

As car manufacturers strive to reduce EV charging times in order to make the ‘refuelling’ process more akin to that of a conventional car, the power requirements of the chargers are increasing. Early rapid chargers were in the order of 50kW to 100kW; however, the latest generation is already up to 300kW. When contrasted with a typical SME power requirement of 80kW, the scale of the issue becomes apparent. Whilst an SME would more likely install slow charging infrastructure in the range of 3 – 7kW each, in selected circumstances we are already seeing some organisations planning for rapid charger installation. In one particular instance, rapid charging will necessitate a capacity upgrade some 30 times that of the current supply. Such an upgrade is not a paperwork exercise and will require major network reinforcement, at significant cost.

Those installing slow charging are not necessarily immune from such issues. Whilst a single 3kW charging point may have little impact on a premise’s electricity supply, 100 such charging points will. Even if the necessary capacity is present, the next issue becomes the electricity consumed. A single 3kW point charging an EV for eight hours will consume 24kWh, currently costing around £3 a day. When a single employee asks for an EV charger to be installed, a business may well be happy to absorb this energy cost. When half the workforce has an EV, will that same business be happy to absorb the cost of firstly installing the charging points, and secondly the energy consumed?

If that one employee becomes 50, the daily electricity cost rises to £150 and over the course of a year that cost is over £35,000. It may be easy to think that the scenario described above is a long way off, but the automotive market is shifting.Governmental policy and simple economics will see increased EV adoption rates as vehicle costs fall, choice widens, and battery range improves. Some in the industry are already citing that the current crop of ‘affordable’ EVs have already achieved cost parity with their fossil fuelled brethren, when purchase/lease, operating costs and residual values are considered.

Consequently, it is paramount that any business with a staff or customer car park has an EV policy that considers: whether EV charging will be offered and, if so, the number of charging points and power of each; any impact on the existing electricity supply; who incurs the energy cost; and ultimately, if energy costs are to be recovered, how this will be achieved.

Businesses acting now will not only be better prepared for the inevitable question from either a staff member, visitor or customer of ‘Where can I charge my car?’ but may find competitive advantage in deploying EV charging infrastructure. Furthermore, some businesses, especially those that install significant numbers of EV chargers, may even be able to derive an additional revenue stream from applying a margin to the energy supplied, or providing Vehicle to Grid (V2G) services in the future.

Will the grid cope?

Given the increasing demands EVs will place on the local distribution, national transmission and generation infrastructure of the electricity system, there is a very strong possibility that the grid (or aspects of the network) won’t keep pace with the ultimate rate of EV adoption. Consequently, we are likely to see the evolution of smart charging. Instead of charging as soon as it is plugged in, the EV or charger will examine parameters relating to local and national demand, price, signals, time of day, the customer’s charging preferences and battery charge state, and then decide on the most optimal time to charge. Customers who are most flexible around when this happens will probably pay a lower price for the electricity, whereas people who want to be able to recharge their vehicle immediately will be able to do so but at a higher cost.

Mobile battery storage

A natural extension of smart charging will be Vehicle to Grid. V2G describes a system whereby plug-in EVs, including battery electric vehicles (BEVs), hydrogen fuel cell electric vehicles (FCEVs) or plug-in hybrids (PHEVs) have the ability to export electricity to the utility provider. With the EV owner’s consent, a utility provider could effectively draw electricity from V2G connected cars. Owing to the variable output of all sources of electricity generation, especially renewables, the operators of the grid are increasingly looking for providers of balancing services organisations that can either absorb power when generation outstrips demand, or supply power when demand is higher than generation. The batteries in EVs are ideal to provide such balancing, assuming power is able to flow in either direction.

As EVs become more mainstream, the collective capacity of their batteries and ability to store electricity will be huge. Significant numbers of EV owners who allow access to even a small percentage of their EV’s battery will collectively provide an enormous balancing resource that has a significant value.

As with smart charging, V2G will be largely driven by financial incentive – allowing access to a small percentage of the EV’s battery will probably result in the vehicle owner being directly compensated or given preferential energy rates for charging. Such a dynamic system that includes smart charging and V2G will also bring with it operational challenges. EVs will not always charge at the same location through the same electricity supply. Consequently, how the benefits of smart charging and V2G along with the actual cost to charge are apportioned between the vehicle owner and the owner of the charging point and electricity supply are currently unclear.

To achieve smart charging, V2G and appropriately apportion the benefits and costs, the quantity of data analysis and the financial decisions that will need to be taken in real-time will likely necessitate a fully automated process. It will require extensive telemetry throughout the electrical distribution system and in the EV, along with real-time information relating to the electricity price, grid frequency, predicted generation availability, weather data and EV owner preferences.

From an EV owner perspective, the process will need to be sufficiently simple and ideally visual, to allow them to see the status of the EV at any given time and feel in control of the process, regardless of the complexity behind the scenes. In much the same way as the online portals provide customers with complete oversight of their energy status, from simple overview of use and spend to complex analysis, EV owners will need similar oversight of energy use, cost and benefit.

In all likelihood we envisage an app-driven system where the EV owner will set basic parameters regarding when they want to use the vehicle and the range they require, and the system will operate to ensure the vehicle charges sufficiently at the lowest cost by charging and discharging as required. Alternatively, an override would allow maximum, instant charging at a higher price for the faster availability.

Evolution

There is currently a lot of discussion and enthusiasm for behind-the-meter battery storage to provide balancing services; however, this vocal enthusiasm in not seemingly translating into many installations.

Furthermore, we suspect that when EVs and particularly V2G become mainstream, the requirement for standalone storage will disappear altogether. Currently with behind-the-meter battery storage, a business case needs to be built, weighing the battery installation cost against the return from the provision of balancing services. With EVs, the battery purchase has been made anyway as part of the EV (or leased as part of the EV), so using an EV battery for motive power and balancing services would appear to be a much more viable option than investing in stationary batteries for a single purpose. While the battery capacity of a single EV is likely to be much smaller than a behind-the-meter battery, and only a small proportion would be accessible for discharge, the number of EV batteries available will, in time, quickly eclipse the total availability of standalone batteries.

If EV adoption accelerates at the pace many believe, and V2G follows suit, the market for behind-the-meter battery storage could quietly die before it has the chance to become mainstream. The wide-scale adoption of EVs will bring challenges to the electrical infrastructure; however, in many regards, the flexibility afforded by the batteries will in itself go some way to solving those challenges. Furthermore, as electricity generation turns increasingly to intermittent renewables and away from conventional, dispatchable, fossil-fuelled generation, the collective battery capacity of EVs will be key in maintaining a stable, greener, grid in the future.

What we’re starting to see is the tip of a rapidly approaching iceberg. Issues around EV infrastructure and strategy are already impacting some customers and the wider business community needs to be conscious that they will, inevitably, impact them too. Just because you can’t see hundreds of EVs when you look out of the window today doesn’t mean that the rise in their adoption is a long way into the future. It is already happening and there is a real danger that organizations who don’t start planning their EV energy strategy will get left behind.

About the author:

Adam Pigott is engineering manager for Kinect Energy Group.
Based in London, and with 19 years’ experience working in the energy sector, Pigott heads up the engineering arm of Kinect Energy Group’s sustainability team, delivering physicalenergy, cost and carbon reductions to Kinect’s customers. He specialises in the delivery of measured energy savings, frequently without the requirement of investment in new equipment.

Source: Smart Energy International