Changes in the way we store large rapid-access energy are democratising the energy market. This blog touches on a (very) brief history of energy storage, and a summary of current developments and why they are of great interest to the home consumer.
Energy generation and energy storage have always been critical to allow civilisation to plan and prosper. Currently the energy world is in a state of great transition as significant energy storage becomes more readily available at economic prices.
Early energy storage was straightforward. A pile of logs allowed pre-gathered wood to be accessed when it was needed with minimal effort. This was essentially a decentralised system with each user organising their own fuel stores, and remained unchanged for thousands of years.
However, with industrialisation, centralised large-scale energy generation emerged using large stockpiles of hydrocarbons, whether a heap of coal or huge oil or gas storage tanks. These energy stores are vital for advanced societies and provide stable energy reserves, but are not able to respond to very fast energy requirements or sudden spikes in demand. And of course, being hydrocarbon based they are not helping climate change.
Until recently one of the few reliable sources of rapid access energy was a hydro-electric store. When demand peaks, water flows from a high reservoir through a generator creating instant energy and commanding a premium price. When demand reduces and the energy price is lower, excess electricity is used to pump the water back up to the high reservoir in readiness for the next energy demand peak. The round trip of the water experiences energy losses and gives what is called the round trip efficiency and is typically of the order of 70% – 80% (learn more about this and other energy storage technologies).
Throughout the twentieth century, there were few economic alternatives to hydroelectric generation of peak or balancing loads. However, two recent changes have made battery storage a contender for this market.
The first change is that the real price of a whole range of battery technologies has fallen. This enables batteries to be deployed to save money in a home environment as well as large battery farms to give grid balancing capability.
The second change is that cloud based control technologies are emerging that allow the aggregation of large numbers of batteries in different locations to be treated as a virtual battery of large size. This is the kicker for home battery owners. As the technology matures it will allow home owners to sell the ability for the grid to control their batteries as part of a large pool of others as a single virtual battery to help the grid. The benefits of this are many.
- As the total available battery storage grows, the peak generating requirement can reduce as the short-lived peaks can be met from stored energy.
- Domestic and commercial battery owners alike can find additional income streams for their investment, while the grid does not need to fund all of the storage itself.
- As renewable generation grows, the available energy can be time-shifted to make it more useful i.e. solar energy can be generated in the middle of the day and used in the evening. Windy night energy can be stored to boil our kettles in the morning. Hence more of our energy mix can be renewable and so help reduce our carbon footprint.
- These factors combine to save us money.