Energy storage systems can go beyond helping sites overcome grid constraints – and second life systems offer even higher environmental benefits. Matthew Lumsden, CEO of Connected Energy, explains more.
The concept of energy storage systems is not new to facilities and estates managers. However, the technology has evolved beyond meeting basic energy requirements for buildings. Thanks to more sophisticated management systems, energy storage can now solve more problems and even play an integral role in delivering a smart microgrid.
Supporting decarbonisation
Many organisations have set ambitious targets for reducing emissions from buildings and much of the low-hanging fruit like LED lighting and HVAC systems have already been picked. The next phase of the strategy will require more substantial investment – and battery energy storage systems (BESS) can often prove the most cost-effective option.
We are increasingly seeing public and private sector organisations looking at decarbonisation in a different way. In the past, green measures had to deliver a financial return on investment. But more commonly now, clients’ calculations are based on the environmental ROI – typically expressed as the price per tonne of greenhouse gases saved. In these types of calculations, BESS can either be a stand-alone option or an enhancer of other technologies.
Here are five ways that BESS can support decarbonisation:
- Green grid energy
A BESS can help you use more green energy from the grid – and also save you money. This is achieved by programming the BESS to draw down energy during quiet periods, when the grid supply is at its greenest, or cheapest, then provide it as needed. This is the most straightforward way to use energy storage, but it can also solve other problems created by decarbonisation strategies.
- Electrification
There are two key strands to electrification – heat pumps and electric vehicles (EVs). For the purposes of energy management, they both have the same impact, as they are high load items. In layman’s terms, they are energy-hungry, for example a 22kW EV charger uses the equivalent power of around 100 desktop computers.
What this means for many premises is that, at some point in their electrification of heat and vehicles, they could experience capacity challenges and the extra investment that requires. Capacity was not an issue during the early phase of vehicle electrification as most sites only required a small number of EV charge points, so demand rarely exceeded capacity.
However, in many areas the grid infrastructure is not yet robust enough to support mass adoption of electric vehicles (EVs) and other high load items like heat pumps. A lot of commercial premises are on a shared connection and typically have a limit on how much power they can draw down from the grid. For sites on half hourly meters, this is known as a kVA allowance, or agreed supply capacity (ASC).
As we move into a phase of mass adoption of EVs, coupled with growing use of heat pumps, organisations are increasingly at risk of breaching their ASCs. This is because EV charging causes significant spikes in demand, particularly when multiple vehicles are plugged in at the same time.
The latest generation of smart EV chargers do offer load balancing to try and mitigate this, but reducing the rates at which the vehicles’ batteries recharge is not always operationally feasible. It’s fine if a pool car needs a top-up charge, but less useful if you are recharging a fleet of delivery vehicles to get them back out on the road.
If you breach your kVA, you will incur penalty charges from your energy provider. Known as DCP161 notices, these charges can be more than four times their tariff rates. We have worked with companies who were incurring charges running into tens of thousands of pounds per year.
This creates a conundrum for many companies, as cancelling or postponing plans to decarbonise is not an option. There are four ways to overcome this challenge. Firstly, paying your distribution network operator (DNO) to increase your ASC limit. The problem here is that in some cases there simply is no more water to draw from the well. Your building is probably sharing a grid connection with several others, and your neighbours are likely to be experiencing the same issues – everyone wants extra capacity. This is increasingly occurring, as a business realises that its neighbour on the same shared connection has already taken the available spare kVA allowance.
If there is no spare capacity, you can only proceed with heat pumps and EV charger installation if you pay the DNO for a connection upgrade. However, a DNO upgrade can run to hundreds of thousands of pounds - plus DNOs are facing a deluge of such requests so there are substantial waiting lists, making this doubly unattractive.
The third way that is worth exploring is a BESS. These systems can help bridge the “power gap” on a site in a more timely and often more cost-effective way than upgrading its grid connection. In this scenario, the BESS acts as a reservoir, drawing down energy from the grid when it is cheaper or greener, then providing it as required during working hours. The BESS provides additional power to meet spikes in demand without breaching your KVA allowance.
The fourth way is to generate your own energy on site – but BESS can help here, too.
- Solar optimisation
Rooftops are ideal real estate for solar PV installations, and generating your own power on site can be very cost-effective.
Solar providers are experts at right-sizing a PV installation to meet your energy requirements – but sometimes demand fluctuations can make this tricky, particularly as you start adding more high load infrastructure such as EV chargers or heat pumps. This can leave you with an excess of energy you can’t use, and that solar surplus extends the payback period for PV.
At Connected Energy, we worked with one client on a multi-building site who was exporting 15% of their solar energy back to the grid. After installing an energy storage system, they were able to capture that surplus and use it to both power their building and help charge their electric vans overnight. In this way, BESS can help improve the financial and environmental ROI of solar installations.
- Second life
While battery energy storage can help your clients with the next phase of their decarbonisation strategies, it is important to also consider how green the BESS is itself – especially in light of corporate decarbonisation targets.
Most BESS use new lithium batteries, which come with their own environmental impact due to the mining of precious metals.
If sustainability is one of the factors behind you buying a BESS, then you might prefer to procure one that uses second life batteries rather than creating new ones.
Giving batteries a second life realises more value from the embedded resources and displaces the environmental impact of new battery production. It delays recycling until the industry has developed more efficient and cost-effective processes, while also improving the overall economics for our transition from fossil fuels to EVs.
Research commissioned by Connected Energy from the University of Lancaster has calculated that second life storage units provide a positive carbon benefit of 450 tonnes of CO2 emissions for every 1MWh installed, compared with a first life energy storage unit.
- Smart microgrids
BESS use a highly intelligent management system which takes their potential beyond being merely batteries to become the “brains” of smart microgrids.
Along with providing local load balancing at scale, a BESS can bring together building management systems, on-site renewables and high load items like heat pumps and EV chargers to create integrated infrastructure.
In addition, when renewable electricity is abundant – either from on-site renewables or the grid - the BESS can fill up its batteries. However, when the grid experiences spikes in demand, the BESS can inject energy back into the grid to help balance the load and smooth out fluctuations.
If your site has a sufficiently high export capacity, BESS can also help improve local grid resilience. The system can take part in grid balancing services – the grid operator pays organisations for this; therefore, it creates a revenue stream.
Timely solution
BESS are increasingly deployed as problem solvers because time is of the essence when it comes to electrification. Councils, NHS Trusts and large corporations have all set milestones and deadlines for decarbonisation. BESS can be the tool to help those organisations to meet their goals – and using second life systems can further strengthen the sustainability of energy storage.
Matthew Lumsden is CEO of Connected Energy, a leading provider of second life battery energy storage systems. For further information, visit https://connected-energy.co.uk/.