The decarbonisation of energy use through a focus on cleaner generation sources can only reduce CO₂ emissions so far. In order to best utilise low carbon energy, strategies for new developments should consider the role of energy storage. This is not a new concept (Economy 7 storage heaters are a well-established form of storage), but the increasingly dynamic performance of grid electricity makes storage more important than ever to achieve cost and carbon savings.
The current thrust for the decarbonisation of energy supply is routed in electricity generation. Energy storage systems enable developments to store or use electricity at a time which is most beneficial, both in terms of CO₂ (i.e. sunny/windy periods for solar/wind generation) and cost (charging storage devices from the grid when prices are low). The use of on-site storage systems also reduces peak demands on a network, therefore reducing pressure on distribution infrastructure.
The carbon intensity of mains electricity is not fixed, varying throughout the day due to the changing generation mix. Importing electricity from the grid when the price is low tends to align with when renewables are supplying most readily. Charging storage systems with this low cost and low carbon electricity can then be used to supply both heat and electricity to residents in a way which is also both low in carbon and low in cost.
Energy storage systems come in a variety of forms. For example, both batteries and thermal stores could be installed on a development to store renewable energy generated from an onsite solar PV array, with additional electricity being imported from the grid during off-peak periods when prices are low. The addition of smart control systems and new advances in storage technology, such as phase change materials, will also assist further with the integration of storage systems into local energy networks.