Can you save on electricity with a portable power station? This is what I learned after a month of use

With the ever-rising prices of electricity, some manufacturers of high-capacity portable power stations (the ones you usually see in RVs) began to promote their products, especially those equipped with panels solar that do not require a connection to the power grid, as an option to save on the electric bill by using them to power small appliances and devices at home. I must confess that curiosity got the better of me. Do people actually use them for this? Is it useful and practical? Does it really help to save money? Do they work with any device? I decided to put this theory to the test with a washing machine, a portable induction cooktop and a computer.

Easy setup

The tests began a month ago, with a 512Wh battery with a 500W output (expandable to 1000W), accompanied by a 220W bifacial solar panel (this means that it also generates energy from the rear). The setup does not take long: in this case, it took me less than 10 minutes to have the battery charging in the sun. That is all the time you need to remove the two components from their respective boxes and connect them to each other. The model I have been using (an EcoFlow RIVER 2 Max) is the size of a car battery and has two plugs and some USB ports, so you can connect different devices to it. In the middle there is a color display that shows the status of the charge or the remaining autonomy time, depending on what it is being used for. There is also a mobile app that also lets you see the status of the charge or how much time is left until it is complete.

The first time it took about five and a half hours under direct sunlight to fill up, but not every day was the same, depending on the presence of clouds; it even took eight hours once. Before using it, I had to analyze the power and consumption figures of home devices with a calculator in order to see what exactly it could be used for. For example, the approximate consumption of a dishwasher is between 900 and 2300W; an oven ranges from 800 to 1200W; an induction cooktop, between 900 and 2100W; and the washing machine between 1500 and 2000W. This means that this battery would not be suitable for the appliances whose use carries more weight in the electricity bill. However, it could be used for a refrigerator that consumes – in their most efficient versions – around 600W per day, or a television set, estimating a consumption of 150 to 400W. So what happens when you plug something and the battery is not right for it? It simply shuts down with an “overload” message.

The first tests were carried out with the desktop computer and the monitor I usually work with. The battery was fully charged, and with a consumption that remained stable at approximately 63W, I managed to work for about 5 hours. Afterwards, I used it to dry and iron my hair, laminate some crafts, heat food in the microwave... I continued like this every day for a full month, trying different devices.

Here are some more details about its autonomy: if the consumption is 140W, it will last up to 3 hours; 300W mean a little less than an hour and a half of autonomy; and the total 800W of the battery, approximately 20 minutes. In conclusion: it is more than adequate for charging mobile devices, using a computer, drying your hair or using the microwave for a few minutes. However, it is not suitable for a washing machine or a dryer, and it was not the best for cooking on a portable induction cooktop.

So, yay or nay?

A few days ago I, received the electricity bill. With 15 KWh less consumption, the cost difference with respect to the previous month was of little consequence; no conclusions can be drawn from this.

This did nothing but reaffirm my opinion about using these batteries at home: it is not a practical system. They weigh little, but carrying them around and keeping an eye on how much autonomy they have left is uncomfortable, as is having the solar panels outside all the time – because you have to charge them every day. As if that were not enough, the price of a battery of this type, with its solar panel, is no bargain: the Ecoflow set requires an investment of approximately $1,250 (including the battery and the solar panel). Other brands, such as Anker or River, have similar prices.

Maybe I would go for an option that involves a permanent installation, that is, if it could always be connected to the solar panels and the device that you need powered at the same time. In a case like that, the firm promises that it can provide up to 1.5kWh per day, although we have not been able to test this. It is also interesting as an uninterruptible power supply system, always connected to the electrical current: in this way, in the event of a power outage, the computer or the aquarium filter – for example – would be able to keep working.

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