Run a Heat Pump Dryer, 1.90kWh Rated 800W with wind

[Data stream]

Hey folks,

I am wondering if it would be possible to run a Heat Pump Dryer, 1.90kWh Rated input power 800W once ever now and then from batteries that are charged via a small wind turbine up on the roof, I'm in a great location and it's pretty windy all the time, maybe not so in the summer but then the clothes would be dried outside or on a clotheshorse, I was wondering if I got an inverter rated maybe 1000w and said batteries would this be possible.

I'd been looking at the following :

Streetwize 1000W Modified Sine Wave Inverter
MOES Smart Dual Power Controller 80A 16KW Automatic Transfer Switch for Off Grid Solar Wind System ATS DC 12/24/48V AC 110/220V

I was thinking that a 12v battery would do the following, 1200Wh÷1000W=1.2 hours
Inverter Battery Capacity (Ah) = Power Requirement (W) x Backup Hours (h) / Battery Voltage (V)

I know there's loads of posts about buying a Anemometer, but honestly it's always windy here! well mostly! but it's just to charge the batteries and I don't use the dryer very much.


Dryer Energy Requirement:

Rated input power: 800 W.
Dryer runs at 800W continuously for 1 hour.
Energy required per hour:
800 W = 0.8 kWh

Battery Specifications:
A typical 12V car battery has a capacity of around 50Ah to 100Ah (amp-hours).

Energy stored in a 12V, 50Ah battery:
Energy = 12 V × 50 Ah = 600 Wh = 0.6 kWh
Energy=12V×50Ah=600Wh=0.6kWh.

For a 12V, 100Ah battery:
Energy = 12 V x 100 Ah = 1.2 kWh
Energy=12V×100Ah=1.2kWh.

Assume inverter efficiency of 90% Energy Available from Battery:

Only 50% of the battery capacity should typically be used (to prevent deep discharge, which damages batteries)
Usable energy from a 50Ah battery: 0.6 kWh x 0.5= 0.3kWh.
Usable energy from a 100Ah battery: 1.2 kWh x 0.5 = 0.6kWh.

Energy Needed for the Dryer:
If the dryer runs for 1 hour at 800W, the energy requirement is 0.8 kWh.

Number of Batteries Needed:
For 50Ah batteries: 3 batteries.
For 100Ah batteries: 2 batteries.

This calculation is for 1 hour of dryer operation. If you need longer runtime, multiply the battery count accordingly.


Thanks

 

[Geoff1946]

Why? It's basically feasible but uses a lot of expensive hardware to achieve little. You wouldn't want ordinary car batteries as they don't like being fully discharged.
If you price up the gear and assume (say) a fifteen year life I think you will find it rather expensive electricity.
If you need independence from the grid, e.g. a boat, then perhaps a different matter.

 

[Richard-the-Ninth]

The first thing you must do is check the wind speed in your proposed location, you may think it's windy, but for a wind turbine to be of any use you need a constant wind speed buy an anemometer for less than £10 Click HERE (What is £10 if you are going to spend £500?)

I found a 400w wind turbine (Just for example) it requires a wind speed of 13m/s Click HERE

Now the maths. (All parts are chosen at random)
Wind turbine £200
Inverter £100
Battery £100
Miscellaneous £100 (Pole, brackets, cable etc)
Total £500

Your dryer uses 800w Lets say 1000w for ease of calculation.

1000w to dry a load in 1 hour is 1kwh

The "average" cost of electricity is 30p/kwh
Your spend is £500.00

50,000 (Pence) / 30(Pence) = 1666 Hours
1666 /24 = 69 days

Which means to break even you are going to have to run your dryer continuously for 69 days

It will be cheaper to NOT spend the money, and to run your dryer via the mains.

You will also have to mount the turbine on a pole, they can become noisy, you will also have to find space to mount the equipment required. Yes, it will be an interesting project, but will it be worth it?

As Geoff1946 says, if you were isolated then maybe, not to mention wind turbines are noisy. I once got a wind turbine for here, just to "test/see what it could do" The answer was it wastes money, I never got an anemometer (I wish I had) the turbine never even moved unless it was a "gale" not doing that again. (And I only got it so I could run a light at night for decoration)

 

[binky]

Cheap turbines are basically useless, and likeky to fall apart in under 6 years. You need much more battery capacity, I would say double, as batteries don't like to be discharged below 80%, and you want a pure sine wave inverter, again over spec it like the battery, with very good cooling to cope with running a load like that.

So it can be done, but...

 

[Data stream]

OK, project shelved. Thanks for all the input, interesting to see the working's out - thanks everyone.

 

[ProDave]

If you want to generate power to reduce your electricity bills, solar PV is much simpler, reliable and cost effective.

 

[binky]

OK, project shelved. Thanks for all the input, interesting to see the working's out - thanks everyone.

I've looked at small wind turbines many times, they just don't stack up. The only time I've ever bought one was for a stable block with no mains available. I fitted two solar panels, with the turbine as basically winter back up for those. Ie when it's cold dark and cloudy mid winter, the turbine would help top up the batteries. Seemed to work fine for that, but loading was a few led lights, possibly boil a small kettle,and charge up some tool batteries.

 

[roys]

B&Q tried to sell wind turbines that fitted onto the side of houses (Windsave I think it was called), it was a flop, no clean laminar air round about houses to drive the turbine, noise and damage caused to the house as it was bolted straight onto the house, and they just didn’t generate very much, think they were about £1000 and did the grand sum of nowt.

 

[Richard-the-Ninth]

Not everyone who wanted one actually got it. There is a video on YT of a "reporter" who goes into detail of it. In short he paid for one, a bloke came round to do a survey, and the reporter heard no more, so he complained, a second bloke came round and actually did some checks, and told the reporter he will not be getting a wind turbine as the wind speed in his location is too slow. But this took several months. I think the cost was closer to 5k not 1K

 

[roys]

It certainly didn’t work out well for the customers or B&Q, in short in my humble opinion wind turbines should not be fitted to a standard house, (there will be exceptions of course) it is doomed to failure

 

[binky]

Not everyone who wanted one actually got it. There is a video on YT of a "reporter" who goes into detail of it. In short he paid for one, a bloke came round to do a survey, and the reporter heard no more, so he complained, a second bloke came round and actually did some checks, and told the reporter he will not be getting a wind turbine as the wind speed in his location is too slow. But this took several months. I think the cost was closer to 5k not 1K

cost was £1.2 k from memory, but life of turbine was about 6 years, so it just about paid for itslef before falling apart.