The share of co-located energy storage (generally referred to as wind and solar energy storage) in the UK market is likely to grow, with 7.2GW of projects currently under development.
Combining solar or wind with energy storage in the UK is still at a fairly early stage of development, with less than 10% of its 1.7GW of battery storage systems already in operation co-located with wind or solar, totalling 158MW. Most existing co-located energy storage projects are connected to two separate grids with a limited amount of infrastructure that can be shared between them.
However, there are currently 317 projects co-located with solar or wind, totalling 7.2GW, or about a fifth of the total.
Project developers are increasingly considering developing shared energy storage, but this presents a myriad of complex challenges. "Obviously, you need to provide input capacity for battery storage, which is a challenge because adding capacity to your existing grid application that needs to be imported can put you further down the queue, which is bad," the developer said. .In order to maximize the return on investment of a co-located project, the battery needs to find various sources of income, depending on the capacity of the grid. Let's say you already have a PV project under development, and the project has a grid-connected Quote, when you want to add energy storage, you need to increase the input capacity, which may delay the date of grid connection, so you need to fully understand how to deal with these kinds of problems.”
The off-take agreement is the real complex part, and most importantly, for long-term owners, it needs to be as simple and risk-reduced as possible.
"You can combine traditional power industry 5 or 10-year power offtake agreements (PPAs) with AI fully automated trading and bidding strategies designed for battery storage, the question is how to achieve this," the developers said. From legal entities You don't want to have two separate contracts that conflict for the grid connection and then start blaming each other if something goes wrong, that's not attractive from a long-term owner's point of view. So you need Find a way to make the responsibilities, assumptions and potential risks clear and minimised."
“Ideally, there is a contract that offers two things at the same time: long-term stable off-take prices for electricity within the company, backed by the corresponding assets, and the ability to implement something novel with batteries that can be used on the grid. The benefits are realized in terms of flexibility.” But contracts of this kind are rare in the UK market.
Most co-located energy storage projects are paired with solar photovoltaics, as wind power tends to require more cycles and larger capacity batteries.
Some sources said that when the market shifts more towards electricity energy trading, energy storage could be paired with wind power in a few years, and about 80-85% of battery storage's revenue currently still comes from grid ancillary services.
