A five-year-old home energy system demonstrates that combining automation with human oversight yields the greatest cost savings, highlighting the limitations of software-only solutions amidst dynamic household needs.
A home energy system built in 2022 to follow wholesale electricity prices has now entered its fifth winter, and its creator says the biggest savings still do not come from software alone. The system was designed to shift the timing of the household’s heaviest loads, including water heating, underfloor heating, electric radiators and car charging, after the electricity crisis exposed how much could be done with automation. Yet, after several winters, the lesson has been that code can only do part of the job.
The programme can read spot prices and choose the cheapest hours of the day. It can decide when the water heater should run and when the car should start charging. That kind of shifting is exactly what a growing number of energy-control services now offer, from heat-pump scheduling tools to smart charging apps that link home devices to live electricity prices. But the article’s central point is that a household is not a spreadsheet. It does not live by price alone.
A system cannot know that the family will be away all day tomorrow, or home all day today. It does not know how much hot water is needed, or whether the car battery must be full by morning. For that reason, the maker argues that automation needs an easy manual override. If software has left consumption on an expensive hour, the user should be able to switch loads off quickly, based on what is actually happening in the home.
That distinction matters because saving on spot-priced electricity is really a two-step process. First, as much demand as possible is moved into the cheapest periods. That is the part machines handle well. The second step is harder: cutting or postponing use that still lands in expensive hours. According to the article, this is where the largest extra savings often appear.
The water heater is a clear example. It does not have to heat every night. If little hot water has been used and the next night is costly, heating can wait until prices are lower. Electric vehicle charging works in a similar way, but on a much larger scale. Because the energy involved is so much greater, shifting charging hours has a bigger financial impact than switching off many small appliances.
In this home, the calculation is also affected by lower night-time transmission charges, which reduce the cost of power after dark. There is not yet a capacity charge, or peak-power fee, in place for the household. If one were added, the optimisation rules would have to change again, because the system would then need to avoid not only expensive electricity but also large demand spikes. That broader trend is already visible in the market: Finnish and European services are increasingly combining price-based control with load balancing, solar integration and device-specific scheduling.
The owner’s rough estimate is that the set-up saves about €1,000 a year compared with a fixed contract priced at 9 cents per kilowatt-hour without automation. For what began as a coding project during the energy crisis, that is a substantial return. It is also a reminder that the best results in home energy management come from combining machine logic with human judgement.
Disclaimer: This content is intended for informational purposes only. Readers are advised to exercise their own judgement, conduct due diligence, or consult a qualified expert before acting on any information provided.
