
EXCLUSIVE by Scottish Energy News
A demand-response energy trading company set up two years ago has used its hi-tech trading systems to scoop a commercial bargain by re-charging its 45MW battery-storage capacity free of charge from three Scottish wind farms.
Limejump – which is based in Brixton, south London – recently added an additional 20MW of National Grid-tested battery-storage capacity – giving it a market share of more than 40% of the UK active battery capacity.
Exploiting this battery expertise and its Cloud-based trading abilities to manage these assets on the wholesale market, Limejump recently benefitted from negative system prices to charge their batteries to make a profit and helping to balance the system.
A mismatch between electricity supply and demand results in a system imbalance that must be swiftly rectified to keep the lights on. Businesses are paid to decrease their demand for short periods of time to help restore grid balance.
A spokesman for Limejump – which this year was a Bloomberg New Energy Finance Pioneer Award winner – explained: “On 3 May 2018, a period of higher than forecast generation from both solar and wind drove the system prices negative.
“Solar was under-forecast by 17% and wind by 27%, bringing 2GW of unexpected generation onto the grid.
“Three Scottish wind farm electricity generating sites at Clyde, Kilbraur and Beinn Tharsuinn received instructions from the grid as part of the balancing mechanism to reduce generation.
“Kilbraur and Beinn Tharsuinn were called to reduce generation because of grid constraints but Clyde was instructed to reduce its output to help the National Grid manage the excess of renewable energy.

“This had the effect of pushing system prices, reaching -£69/MWh for two half hourly settlement periods (1 hour).
“Spotting this opportunity, we charged around 45MW of batteries, reducing the amount of excess renewable energy that would otherwise be wasted, helped the grid deal with the excess supply that was then delivered back to the grid when prices were high and when there was limited generation on the system and all whilst optimising battery revenue.”
Limejump manages the largest portfolio of batteries in the UK and aims to develop a ‘virtual power plant’ going forward.
Its main Scottish-based rival is the low-profile demand-response competitor, Flexitricity, which operates from Edinburgh.
23 May 2018