KNX Hackathon Finalist: The xxter Smart Energy Manager Reduces Consumption by up to 30%

xxter developed the KNX-based Smart Energy Manager (SEM) that not only monitors energy usage and production, but smart-manages it too. Based on the energy production forecast, which can be automatically predicted with impressive accuracy based on factors such as the weather forecast, dynamic pricing information and the customer's typical needs, the best schedule is created to minimise energy consumption from the grid, thereby reducing costs and the carbon footprint.

An example of such scheduling would be to charge an electric car when there is a lot of solar energy available, or when the spot (hourly) electricity prices from the supplier, are low. The xxter SEM can also manage home batteries automatically in order to further improve the efficiency of self-produced energy.

In order to prove what kind of savings can be made using this technology, xxter first made some general calculations using publicly available data in The Netherlands. They based this on several scenarios, and all were calculated during the whole of 2022. xxter acknowledges that, owing to extreme global events, the prices for 2022 might have been atypical, but given the dynamic pricing tended to be higher as well, this should not affect the results too much, and the principle remains the same.

In all scenarios, xxter compared 'static' situations with dynamic spot prices and single- tariff prices with a similar calculation in which the SEM would have managed a part of the energy usage with a dynamic contract.

The scenarios calculated were:

• A single 800W pump for a pool,which needs to run for several hours a day (which hours are not very relevant, so this can easily be managed by the SEM).
• A small electric car which is not used every day, charged twice a week to 50%.
• A medium electric car which is used almost every day for commuting, charged daily to 50%.
• A hot water boiler which is set to a higher temperature when prices are cheap and lower when prices are high. It was assumed this would only be used for showering for two people, each for 5 minutes daily.

In all situations we made some basic assumptions such as that car charging would start at 18:00 when someone would come home during the 'static' situation, and where the car would be charged dynamically using the SEM between 18:00 and 06:00 in the morning.

In addition to its own theoretical calculations based on real-world pricing, xxter has been using 20 beta testers since February 2023. The exact details cannot be shared due to privacy issues, but their experience seems to corroborate our calculations.

At the time of writing, February is only a few months ago, so there is no long-term data yet, but the feedback is very promising. In particular, the SEM, in combination with KNX classic devices, electrical car chargers and solar panels, results in the highest reduction of costs. The beta testers experienced a reduction between 8% and 35%, but these are on a month-on-month comparison with kWh usage. Of course the results will vary a lot month to month, and user to user.