Solar Panels

Hexane

Martyn1981 said:

Hexane said:

Bowsa said:

13 sounds like quite a lot, this is where I am struggling as I don’t know how much energy to expect…..

12 x 350W panels will generate just over 4kW under ideal conditions (a cool but cloudless midsummer day) but on typical installs the inverter will limit that to 3.68kW.   (Note: panels of 400W or more are now commonly available.)

If you're generating 3.68kW then you can be running your tumble dryer on full blast (3kW) and then whatever other LED TVs, radio, internet router, alarm clock, laptop, phone chargers, the clock on the oven etc., at the same time all for free. But if you then turn on a 3kW kettle as well then you are going to be several kW short so you will be paying for the shortfall by buying energy from the grid.

So your choices are either:
1. accept that for that small amount of energy you're going to have to pay
2. accept that you're going to have to wait for the tumble dryer to finish before boiling the kettle
3. pay extra for a bigger solar generation system
4. pay extra for batteries suitable to supplement generation in that situation
5. some combination of the above

if it's a cloudless midsummer day then maybe you won't need to use the tumble dryer anyway though!

For comparison purposes, the heating cycles on our dishwasher and washing machine both draw about 2kW each (but not for especially long periods of time), a top-end games console or gaming PC or a big plasma TV might draw some hundreds of watts each, and most laptops, phone chargers, internet routers etc draw basically negligible amounts of power for these purposes.

The heating element on our electric oven draws 3kW when heating up to temperature or heating to return to temperature.

An electric car charger can typically use 7kW ...

One other option (not being picky, great list) is to spread the load out over a longer period.

Explanation for non-PV'ers:  So for instance, put the tumbly on low heat setting, and get a travel kettle. I have a 1kW kettle (birthday present / joke from Wifey years ago), use it all the time, as it boils one mugs worth, so no wasted heating. The lower but longer load solution helps to prevent or minimise import but spreading demand out and trying to keep it within the amount being generated.

Ah yes, there are some measures that depend on "local conditions" to be implemented. For example the clock on our oven doesn't draw any power at all when the oven isn't in use, but that has the side effect of the clock on the oven always being wrong - because we power it off completely. I can get away with that, but using low heat setting on the tumble dryer would involve reading the instructions, and that won't happen.

There are also heat pump tumble dryers - at two or three times the cost of an ordinary condensing tumble dryer - that probably draw far less than 3kW even on maximum power.

This winter we might investigate running the dishwasher on something other than "Intensive" program finally.