Micro Wind Turbines
Posted 23 September 2015 - 10:10 AM
I appreciate that on a small scale, its never going to produce an epic amount of power, but was thinking more of a top-up to go with the Solar PV.
Looking on eBay there are UK sellers selling 400W turbines for about £150, not including all the other bits you likely need, and they work from as little as 2.5m/s wind. How likely is this to provide any decent amount of power?
Having a 4kWp Solar PV array, would I be going over the G83 thing I've seen people talking about? Would this be able to tie into the sunnyboy inverter where my Solar PV is connected to if it has a 3rd phase?
Its probably a none starter, but just thought it worth revisiting.
Posted 23 September 2015 - 10:24 AM
The other thing about micro-tubines is that they dish out very little power. Cutting in at 2.5 m.s-1 just means they are generating something, nothing like the maximum rating. That will be at much higher windspeeds. So high generally that that they really happen for any length of time.
I was at a place on the weekend that had an Eclectic Energy turbine, http://www.duogen.co.uk/, the owner spoke highly off it, but I did not ask what the annual yield was. Probably not much if the truth be known.
You could directly connect one to a resistance heater of some sort, just let it store thermally when it is generating. Jeremy knew someone that did this, they used a pile of rocks and rubble in the building as they store.
Edited by SteamyTea, 23 September 2015 - 10:26 AM.
Posted 23 September 2015 - 11:01 AM
If you're in a rural area and can put the turbine 10m up at least, and 30m from any significant obstructions, then generation conditions could be good.
Have a look at fieldlines.com (on which I am a mod) which exists to talk about small wind gen, but where I'd say a majority would now suggest PV first in most situations, from a generation and maintenance point of view.
I experimentally had one in my garden, which I am doing without this winter, and I think it was not even turning 1% of the time, never mind contributing significant energy, whereas I generate many megawatt-hours per year from a grid-tie PV system and run an entire server system off a separate off-grid PV system, in our small suburban plot.
Go into it with your eyes open.
Posted 23 September 2015 - 11:05 AM
Posted 23 September 2015 - 11:08 AM
Posted 23 September 2015 - 11:13 AM
Posted 23 September 2015 - 02:25 PM
Large wind turbines have a very much wider range of working wind speeds, because of the ratio of fixed losses (friction etc) to output is much smaller, but even the very best can only extract around 50% or so of the potential energy in the wind. There is a hard limit with efficiency that has nothing to do with electrical or mechanical design, but is imposed because to work, a wind turbine has to have air flowing through it, which means the air must still be moving on the downwind side. If the wind turbine could somehow absorb all the energy in the moving air, then the air would be completely still on the downwind side.
Using aerodynamic devices, be they rotating blades in any form or sails or whatever, relies on there being moving air, so this type of device, in any form, can never extract all the potential energy. If you came up with a device that didn't use aerodynamics, but somehow managed to intercept an area of moving air, stop it dead and extract all the energy out of it, then you could probably double the efficiency of wind turbines. No one has done this yet, though.
Edited by jsharris, 23 September 2015 - 02:26 PM.
Posted 23 September 2015 - 03:19 PM
Get them if you need one, silent is remarkable!
Posted 23 September 2015 - 04:39 PM
There are lots of ex F1 designers. The good ones are still doing it
Posted 23 September 2015 - 05:20 PM
Posted 10 March 2016 - 07:25 PM
Whilst wind turbines are not as efficient as PV they work - when it is windy - for 24 hours a day and that, I think, is their main advantage in a climate like we have in the UK. Because turbines need to be under continous load the surplus power needs to be used, in our case the dump-load is a heating element in a water tank.
Would I have installed wind if we were grid connected? Probably not.
Posted 10 March 2016 - 09:52 PM
Posted 10 March 2016 - 10:26 PM
Posted 10 March 2016 - 11:52 PM
1.55m diameter blades, so not tiny I guess. I'm not sure what constitutes 'micro' although I have seen 1KW units described as such. I think their usefulness depends very much on your requirements and of course the quality of your site.
Posted 11 March 2016 - 09:59 AM
Yes, it's not silent. We don't find the noise offensive though, its a swishing kind of sound. As the wind increases it gets louder but you probably notice it less as the wind through trees etc nearby is louder.
I don't think our turbine is the quietest available, we chose it because it has a low visual impact as much as anything - it is a downwind model with no tail boom made by a company in mid-Wales.
Posted 11 March 2016 - 10:07 AM