Wednesday, 26 June 2024

Saving energy with new appliances ?

I've always been a bit skeptical about the idea of replacing appliances early in order to save energy. The embedded emissions in creating large appliances are not small, so you'd have to make a pretty big saving in ongoing emissions for it to be worth scrapping a device early to install another in its place. Generally speaking, I prefer to repair things and keep everything working for as long as I possibly can. But sometimes it does make sense to buy something new.

Since we moved into our home in the Netherlands 17 years ago we've done a lot to make our home more energy efficient. We've improved the insulation, replaced the windows, built a ventilation system (which I'll write about in due course), removed the gas supply altogether, and installed solar panels to generate more electricity than we consume. But the inside of our home hasn't seen so much work.

The kitchen was a bit tired looking when we moved in, and it's not got any better with almost two decades of use, so this year I've been working on improving things.

The kitchen cabinets were mostly actually still OK but the doors mounted on them, which were made of thin white plastic coated chipboard, were falling apart and they looked super ugly. Rather than throw everything away I've made new doors from scratch to fit onto the old cabinets, and also constructed new cabinets of plywood where they were needed. This is also much cheaper than a complete new kitchen, so it's a better fit with our limited finances. We then had the question of the refrigerator. The old built-in refrigerator was in the house when we moved in and I always had the idea that it consumed at lot of electricity because it hummed almost constantly. Unfortunately, until I started taking the kitchen apart I couldn't reach the socket where it was plugged in and measure it.

Measuring refrigerator/freezer consumption
The old (late 1990s / early 2000s) refrigerator turned out to use a whopping 500 kWh of electricity per year. That's five times as high as some newer models of the same size, small refrigerators without freezer compartments. We also had a freezer which we'd brought with us from the UK. This was a Liebherr unit which was a well rated model when we bought it. I'd looked around and found one of the first devices available which did not use CFC style refrigerants. But I measured the freezer as consuming 250 kWh per year, which is actually not more than some new comparable models. But 750 kWh per year in total for refrigeration is ridiculous.

New A-rated fridge/freezers with a similar capacity to our old fridge and freezer combined are rated as consuming about 110 kWh per year. None of the A rated devices are built in types so we had to choose between free-standing fridge freezers. We chose an Inventum KV2010B as this company gives a standard 5 year guarantee and provides reasonably economically priced parts for repairs.

New and slightly imposing fridge/freezer in our kitchen, next to kitchen units with newly constructed home made doors. For some reason all the A-rated fridge freezers are black. Whatever happened to "white goods" ?

The real world consumption of the KV2010B in our first week works out as equivalent to 190 kWh per year. That's above the rated 113 kWh / year according to the manufacturer. However the standardized tests are carried out, the conditions are clearly not the same as ours over the last week. Of course a week at the end of June is warmer than the annual average and I expect this appliance will use a bit less electricity in colder months (our old devices also consumed less in winter than in summer).

Energy rating certificate for our new fridge/freezer.

The same refrigerant, R600a, or isobutane, is used in the new fridge freezer as in our old freezer. I don't know what was used in the old refrigerator which we didn't choose, but it was probably something horrible. When we bought the freezer this was an unusual refrigerant but it seems to be commonplace now. That's quite an improvement. R600a has a very low GWP (global warming potential) of 4 compared with CFC refrigerants which can be in the thousands. It's not quite so low as the R290 of our heatpump, though.

The value of the electricity saved
We expect to save almost 600 kWh per year with this new appliance in place of the two old devices. That's significant. It's almost as much electricity as we used for all our heating last winter. It's also about the same as the output from two of our solar panels. I think it's worth noting that much of the saving will occur during night-time, on the shorter days of winter, or when there's not much sun. i.e. at times when it's especially valuable for us to save electricity because we don't have so much of it available from our own panels.

In the Netherlands the total retail cost of electricity including all taxes is currently around 25 c / kWh so a saving of 600 kWh of electricity is worth about €150 annually. Having paid €799 for the appliance the appliance should pay for itself in about five years. It will also save 134 kg of CO2 each year (at 223 g / kWh average emissions for NL). The actual cost for us is much more difficult to work out because we generate more solar electricity than we use.

Disposing of the old devices

The people who delivered the new fridge/freezer took the old fridge away for recycling, but they would only take one appliance, so I had to take the freezer on a 7 km trip to the local recycling centre by bike. Both of the old appliances were the same size as this.

At the recycling centre they picked it this way, putting considerable pressure on the radiator at the back and risking causing a leak of the refrigerant. That's why I didn't buy a CFC containing freezer in the first place. I suspect that even when they're supposed to be safely removed, only a small percentage actually are safely removed.


An earlier trip to the recycling centre. Judy and I transporting parts of the kitchen cabinets, mostly rather nasty damaged doors but also the parts which contained the old built-in fridge.

Update: Energy meter problem
It turns out that our plug-in energy meter has a problem. It's reporting 270 V as the voltage of our mains supply instead of the ~225 V which the multimeter reports. 270 V is above the legal maximum supply voltage. I believe the multimeter. Anyway, this 20% high voltage reading probably translates into a 20% over reading when measuring Watts as well, so the first week of the new refridgerator was probably a lot closer to the manufacturer's specification than what I measured.

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