LOW VOLTAGE GRID CONNECT WIND TURBINE now in stock

[Ivan]

Please see website for further details http://www.navitron.org.uk/lowvoltagegridfeed.htm

I have not really had time to put a lot of info up about this unit yet, but if you visit the webpage above you can download the product manuals. The webpage is advertising a complete system, but the grid-tie inverter is available separately for £300.


Ivan

[martin]

oh what a giveaway! - you've left "this auction" in the text!

[east1966]

Ivan, can you please advise a package price for a 500w turbine, 2 Grid Tie Inverters and an AP Box, without the standard inverter normally supplied.

Thanks

[Ivan]

Hi Martin, Damn, you would spot it! Just put one on ebay to see if there is any serious interest there. Same page more or less on the website. The price on ebay is higher than on the website, thus hopefully, I will not be lining ebay's pockets, but it will hopefully drive a little more traffic to the site.

east1966: The price for a 500W 24v wind turbine is £525, 2x300W gridtie inverter low voltage £300x2, and AP box £225  (all including vat)

Ivan

[madandy]

Ivan - at that price (total £1350) for the 500W system, would we not be better off buying two 300W (therefore 600W)systems (total £1300) and connect them independently?

[Ivan]

Yes, indeed - as you would not need the AP Box to synchronise the two grid-tie inverters.

Many small wind turbines are a cheaper option than one larger turbine in most situations - just compare the prices of the larger turbines with the smaller ones on a price-per-watt basis.

The only drawback is that you would have two towers, two turbines, twice as much area of land taken up. Having said that, if one failed for any reason, you would still have half the output.

Ivan

[ecogeorge]

Trying to understand G77 and G83 requirements for grid connect. Does this inverter pass as G83 compliant because of its low output (300w) and therefore classed as an ac module?
Does connecting up to 4 in parrellel invalidate this?
To be technically correct should switched fused spur be double pole and is a  "dual supply" notice needed at the meter?
Not trying to be negative , - fantastic inovation.

[Ian]

ecogeorge - this is how i understand it...

G77 is for high power connections (cannot remember what high power actually means but it is probably something like when you try to squirt more than 3.6 kW back into the grid). Anything under this "magic" figure is taken care of by G83.

I think the posts to date have said that the 300 watt grid tie inverter is not (yet) G83 certified.

Connection of 4 or more would only invalidate G83 once it went over the "magic" threshold (as I said above, I think it is about 3.6 kW)

You are correct regarding the safety stuff for normal circumstances of alternative power supply. Some utilities may require a FUSED separate isolator too.

G83 automatically covers the safety requirements and intrinsically provides the isolation required. As a G83 inverter is incapable of supplying power when the utility is down, there is no real need for dual supply warning notices. However, I think it would be good practice to supply isolators and safety warnings and they would definitely be part of my system.

I hope this helps.

Regards,
Ian

[KenB]

Ivan,

Interesting to see that the grid tie inverters can be paralleled to provide a higher wattage.

I wonder if  you can put two of them series across a higher voltage battery - so each only sees 55V.

This could make an ideal low cost GT inverter for the Lister running in stealth mode.



Ken

[Ivan]

The max input voltage is around 65v - if this is exceeded, damage can occur - so it is important that the voltage does not exceed this.

In standard form, the inverter starts grid-feeding at 24v, and the amount of power increases, as the voltage increases, up to the maximum output at around 48v. This can be tailored to a certain extent, but it would need new firmware to work with 55v. Would it be possible to work at a lower voltage?

[KenB]

Ivan,

If we connected the alternator windings in US style - ie 115V, and rectified this, it would peak at 163V. 

Three of the grid tie inverters could be connected in series across this - each only seeing an input voltage of 54V.

Might be worth contacting the supplier to see if they could be used in this manner - alternatively use a big transformer to drop the output of the ST down to  55V when rectified.

Ken

[Antman]

Ken and thread

The problem with direct series connection is that the inverters will not all 'ramp-up' evenly. Thus the perceived 'load' of each will not be balanced and some will see more voltage than others until all are running.
The ones seeing a 'little more' than their fair share of 1/3rd voltage at power-up will still work - albeit  briefly.... 

Even if it did work, and it would be by luck rather than design, if one inverter sufers output failure, the balance of voltage chain will be lost.

Antman