CheckWatt is now launching CheckWatt AI, a system that uses artificial intelligence to better predict energy consumption and production in a property, optimizing battery usage to create greater value in the form of lower electricity costs. The system’s AI capabilities mean it automatically learns and improves over time, becoming more effective the longer it’s in operation.
Following a successful pilot project, CheckWatt AI is initially being rolled out to all customers who use the recommended Currently Optimized operating mode, and have hourly pricing agreements. For these customers, the battery will be used to perform electricity price arbitrage.
This means that instead of having to worry about high electricity prices during peak hours, battery owners can take advantage of price fluctuations. By using electricity stored when prices were low during peak pricing periods, battery owners can instead benefit from the fluctuating prices.
Maintaining full revenue from ancillary services
To ensure that the batteries can continue to provide income-generating ancillary services to Svenska kraftnät, electricity price arbitrage will be carried out within a limited range of the battery’s capacity, initially around 20–40 per cent depending on the battery’s storage capacity in relation to power – i.e. how quickly it can charge and discharge energy. The greater the storage capacity, the greater the proportion that can be used for electricity price arbitrage. The changes do not affect revenue from ancillary services.
CheckWatt is also working to enable customers without hourly pricing agreements to benefit from price variations by trading stored electricity through balance responsible parties.
Charging and discharging a battery for use or sale puts more wear and tear on it than, for example, providing the ancillary service FCR-D, where the charge level remains relatively constant. To account for wear and tear and energy losses, electricity price arbitrage will only be performed as long as the minimum savings per charge and discharge cycle is approximately €0.04 per kilowatt-hour.
The goal is to implement CheckWatt AI for all residential customers with the Currently Optimized operating mode and hourly prices configuration during January, followed by systems in commercial properties.
The system being launched now is prepared to add capacity tariffs going forward, as well as increased self-consumption of solar energy.
Example of a battery combining ancillary services with electricity price arbitrage
For the battery in the graph, the charge level is limited to between 30 and 70 per cent. In practice, this range will vary depending on the battery’s power and capacity to ensure that the battery can provide ancillary services to the greatest extent possible. Charging and discharging are limited by the consumption in the property, meaning that there is no export.
Increased volatility expected to increase benefits of electricity price arbitrage
In the future, more active and AI-based optimization between ancillary services, local flexibility, electricity prices, and other local benefits will be an integral part of the management for all our customers.
Opportunities for batteries to create value from electricity price arbitrage are a direct function of the volatility in the electricity market, which is predicted to increase in the future. Increased development of solar and wind power leads to greater price fluctuations, and more interconnectors and market reforms, such as flow-based capacity calculation, mean that the Nordics more often import high and volatile electricity prices from Central Europe.
However, ancillary services have been significantly more profitable than electricity price arbitrage over the past year. According to CheckWatt’s analyses, electricity price arbitrage could have yielded savings in the order of €100–200 per year in central and southern Sweden, respectively, for a 10 kilowatt / 10 kilowatt-hour home battery between November 2023 and October 2024. In comparison, ancillary services could have generated revenues of around €500 per year, calculated based on the prices of the Swedish FCR-D up and down ancillary services over the past three months. However, CheckWatt AI will be able to perform both services simultaneously, increasing the battery’s potential.
