It’s almost impossible to overstate how important the growth of energy storage technologies – and we are really talking about electricity storage here – is to the operation of energy distribution systems saddled with increasing volumes of intermittent generation, whether from renewable sources or from on-site cogeneration schemes designed to run to meet local heat loads.
And innovation is coming from more than one angle – storage technology developers and grid operators are being joined by manufacturers of decentralized generation plant in designing generation/storage systems.
Solar power and electricity storage are becoming locked together almost into one concept – solar+storage – where storage allows customers to maximize their use of the energy generated at home or at work without exporting excess power to the grid.
And I have been looking at reports from the UK of new hybrid flywheel/battery electricity storage technology; of battery storage systems being added to wind farms so that what was a pure generation facility now also offers power grid frequency balancing services; and of real-world studies of using the batteries inside electric vehicles to sell power back to the grid at the right time of day or demand pattern.
Now, decentralized generation giant GE has started a programme of adding batteries to its gas turbine peaking power plants run by grid operators to rapidly supply power when, typically, renewables-based plants cannot generate. But even decentralized peaking plant needs time to reach full power, so operators can now – instead of wastefully running turbines at minimum load continuously so as to be ready at all times – connect the batteries to grid when power is called for, simultaneously initiating start-up of the turbines.
Here, the advantages accrue to grid operators but, as GE says, as battery costs fall it will make increasing sense to add customizable battery systems to a wide range of generation plant, including smaller, on-site systems – the secret is in the control technology that maximizes benefit from the two components.
We used to have large central generation plant with one-way electricity transmission and distribution systems. Now, with embedded or decentralized generation, plus energy storage and, crucially, smart grid controls, electricity systems can really be optimized for cost and environmental benefits.