Energy Coast West Cumbria Limited, trading as BEC, invites tenders for the design, manufacture and supply of a factory-integrated, modular Adiabatic Compressed Air Energy Storage (A-CAES) demonstrator plant for the BEST CAES project at Westlakes Science Park, West Cumbria. The requirement comprises an above-ground, transportable system incorporating compression, thermal storage, expansion equipment, compressed-air storage vessels, power electronics and controls, together with specified testing, documentation, training and warranty support. Required performance includes 0.333 MW charging, 1.0 MW discharge and a minimum electrical round-trip efficiency of 80%. The maximum contract budget is £1,600,000 excluding VAT, with operational handover required by 30 June 2028. Long-term paid maintenance and supplementary rapid-response hardware are excluded from this award. The procurement will follow an open procedure and is subject to funding, planning permissions and necessary approvals.