UKC

Domestic wind turbines?

Just wondering if anyone here has got one.

Thinking of getting one in parallel with solar. Definitely diy, as the estimated £25-30k install costs are taking the p. 

I have some experience as we used to live on a boat, off grid with battery and inverter system. 

Live in a windy area, great for kitesurfing etc and why I live here. 

Our house is totally electric, so I'm thinking of it as a supplementary system not totally off grid, but with the imminent energy cost increases, the cost benefits are looking better by the minute. 

Wind turbine, inverter and smallish battery Bank, probably add a bit of solar for the summer but our electric usage in summer is low. 

I haven’t. Bump.

I wouldn't recommend it for any domestic property, unless you have a farm or similar where you can get the turbine away from obstacles that buffer the wind.

If you really want to know, then get an anemometer that logs the speed and compare the average speed to the datasheet for the turbine.

Try making a couple vertical axis if you have the space put a few together, cheaper than £25k

https://opensourcelowtech.org/wind_turbine.html

youtube.com/watch?v=t9TrUPoevXI&

We live in a bungalow, like most of the properties on our road and our garden is long enough to site it a decent distance away. The predominant wind direction is fairly unobstructed.

Issues to think about beyond those mentioned:

• Planning permission - years since I check but IIRC it used to be you only had permitted development rights (ie no need for planning) if it was MCS certified kit and installer (so no DIY) and if you didn’t have an air source heat pump.
• Neighbours.  Sometimes wind turbines are a bit of a trigger…
• Merging a battery/inverter system for load shifting with a grid install is more complex than running off grid as you have to meet various regulations (EREC G whatever) - if you also want an off grid island mode for outages, then needing to be EREC compatible curtails the use use of in-band (grid frequency) signalling to control supply from solar and wind inverters in island mode.

I thought about wind and decided the answer was more solar; the only hassle is snow accumulation on the panels.  The multi day outage after storm Arwen saw me on the barn roof with a broom clearing the snow off…

I’d still love a vertical axis wind turbine for the cool factor, but in our case the money will be better spent on a 750 W run of the river pelton wheel hydro system; this dovetails perfectly with the solar over the four seasons.

We have one on the gable end wall of a semi detached house, rigged with a steel frame, about the height of a chimney stack, installed by the previous owners. The blades are about 2.5 metres total diameter, feeds into a SUN 1000g grid tie inverter that plugs into the mains. Today it’s damp and misty, the blades are just turning slowly, and the inverter says it’s generating 2.4 watts right now. In strong winds I’ve seen it hit 20 watts. It’s not making us any money, for sure, but if it was a battery powered house it’d be making a steady contribution.

I remember reading about a Welsh startup company somewhere betweeen Swansea and Cardiff who’d patented a slender helical turbine for domestic use about 15 years ago. Instead of requiring the wide clearance needed for large blades, or a rotating mount to enable the turbine to face into the wind, the helix twirls around the central shaft directly. You see em around and about occasionally, I keep thinking I should look into it more.

From my memory of looking into vertical axis wind turbines, they are a waste of money even in the urban locations where they supposedly convey advantage from being invulnerable to changes in wind direction. They are not invulnerable to low wind speeds, which you also get in urban locations. Besides which all the examples I see (eg at Roscoff ferry port) from some feted PhD laden start-up are always stationary.

Do you get vibrations in your house from the turbine strapped to it? As was said above, it is probably a very bad idea to have a turbine that only just pokes above roof level since the wind speed there will be low and the wind turbulent.

A much better idea, if you want a wind turbine and can do it, is to club together with your community and buy a huge one stuck up on the village hill.

Building an off grid system was easy enough for our boat. We had a 3kw inverter,  24v 80amp charger and an automatic changeover switch when using the genset with 12000 amp rolls surette battery bank. 

Been looking at grid tied inverters and the current regs for this type of system, seems straight forward enough.

I'm still debating just going full off grid. Maybe just keeping the mains supply for back up battery charging. 

Yes; on grid and off grid are both simple.  Mine was 2 x Rolls and is now 4 x Victron 110 AH AGMs.

Doing a DIY job that’s regulations compliant and works both on grid and off grid is harder.   This is assuming you want a Wind > AC inverter you can grid connect, and that you can also safely use with an off grid battery system.  (The battery system may or may not load shift when grid connected).  When off grid you have to let the battery’s inverter/charger control the wind inverter’s AC power output as it will normally force all power out on AC, but if your batteries are full it has nowhere to go and the microgrid becomes unstable as something shuts down to self-protect.  This doesn’t arise with a DC connected wind charge controller (which directly knows the battery state of charge) but if you move to grid connection you need an AC inverter which only sees the (micro)grid and shoves all power to it, oblivious of battery state of charge when in microgrid mode.

If you have an AC connected inverter for the wind or solar, the problem with a system running in both modes is how you limit the output of the AC inverter when the batteries on the inverter/charger providing the microgrid are full.  For off grid systems, the grid frequency is shifted to signal reduced demand to AC inverters, but the settings this needs for the AC inverter can fall outside of the range needed for grid operations.

If your turbine is connected to the inverter/charger by DC, life is a lot easier for regulating output when in microgrid mode whilst being grid compliant, as the inverter/charger handles that.  

I should have used a Fronius AC inverter for the solar, which my inverter/charger (victron) could have demand controlled via Ethernet instead of in band grid frequency signalling.  The kludge I’ve adopted is that the off grid mode uses a Tristar 45 A diversion controller (to a resistor array) on the battery bank to prevent over charging with an AC frequency sensitive switch mopping up excess power on slower timescales.  

I hope I explained the problem clearly!  Apologies if not.

Do you mean kW?  2.4W isn't much

I saw a youtube video recently of somebody making their turbine blades from wood, really interesting. Looks like he made his own generator too  youtube.com/watch?v=dkJNQMMJwcg&  

Second this. A UK-wide study was carried out a few years back into "micro wind". In most cases the turbines didn't even break even on embedded energy, and very few made any significant inroads into household demand. The report was so damming that most of the domestic wind suppliers slowly faded into obscurity...

That said, you might have a reasonable wind resource. Before committing to any serious thought/spend, as Steve said - get a weather station in there on a mast at the height you'd want the turbine (higher the better, obvs). Track it for a year and then decide. 

Better still, convince your neighbours to get a proper community wind turbine and site it further away in some farm land...

Nope, they are like that. I had the largest one they make for yachts and mostly it just cluttered the boat up, vibrated and had the potential to hurt. When it really blew I had to stop it before it exploded. Best I saw was about 28W.

Junked it.

a 2.5m span produces max of a dim light bulb?  What's the point?

Someone I know who lived at 450 m on the side of a fell would get about 10 kWh/day from theirs in winter.  

Bolt them near to the roofline of a house in an urban area and it's a total waste of money; or worse if the cowboy installers didn't get the anti-vibration stuff right.  

When you sail around the world without an engine they'll power your radio, they were made redundant by solar panels. The rest of us just modified the alternator on our engines and smashed a kW or two into the batteries.