pv generation with no feed back to grid!

[solarsystems]

i have a project at the planning stage at the moment. 100kw across 3ph. dno say that the infrastucture is not capable of feed back, and would need a costly upgrade.

however he says that we can still get the feed back tariff using the pv generated on site but using a controller other than the g59 to prevent feed back to the grid. if anyone could elaborate on this i would be thankful.

 

[TedM]

I guess the DNO are saying you need a system that prevents any export from the site - or at least any export above 16A per phase. You get paid the FiT rate based on what you generate so you don't need to export any. But you would need a load on site that was capable of using all of the 100kW - a dump load (where the power is not usefully used) is not acceptable.

If you export anything at all then the DNO will need to agree the design meets their requirements.

 

[solarsystems]

thanks for your reply TedM. This was my conversation with our customer. The fact that they may have 100kw on the roof but if they don't have the capability to use it then they are wasting there money, as they will only receive FiT for what they use not what the array is generating. any info on who produces a controller to regulate this?

 

[SolarCity]

I'm surprised you're even planning a >50kW install with the reduced FITs.

 

[Worcester]

Does the client plan to do the costly upgrade at any point in time?

If not, then scale it down, if yes, and the dno is happy then you might be able to use the SMA Power Reducer Box system to limit output temporarily.

POWER REDUCER BOX. SMA Solar Technology AG
Background info:
Feed-in and grid security management. SMA Solar Technology AG
SMA inverters as grid managers. SMA Solar Technology AG

 

[Graeme Harrold]

Might be worth investigating hydrogen production for use outwith daylight hours. this may provide a cost effective solution to 24hr power. Solar PV to H2 in storage, the h2 back through a fuel cell to generate power when needed.

 

[TedM]

I think installing 50kW instead of 100kW would do exactly what the SMA power-reducer would do - at a fraction of the cost.

If the power-reducer tells the inverters to throttle back the output then you will not be getting paid FiTs - as nothing/less is being generated.

Looks to me that the practical use of that box outside Germany (where it is mandated) would be very limited unless the legislation changes here.

 

[solarsystems]

this installation has to be finished before FiT changes!!! no pressure! spoke to dno when they said no, he said that there was a way of using power on site and prevent export to the the grid....... BUT wouldn't tell me how or any contact for information!! very helpfull!! what really puzzles me is the fact that the incoming supply main swith is 800A. the max we would feed back is 144A per phase at peak! i think questions need to be ask as to why the need for an upgrade.

 

[DomB]

Just a thought - the EMMA from CoolPower Products might allow you to divert the excess power into other on-site electrical circuits - but what you put on those circuits which does what you want without it being considered a 'Dump' I'm not sure..

 

[SibertSolar]

Thought of this thread when I read about Conergy's new inverter product, I wonder if this might be an option:

SolarIndustryMag.com: Content / Products & Technology / Conergy Introduces Photovoltaic Inverter Unit With Energy Storage Capabilities

 

[JD6400]

Hi solarsystems , was wondering how you got on ?

 

[solarsystems]

Hi solarsystems , was wondering how you got on ?

well! after delay after delay and jumping through hoop after hoop, the DNO allowed us to proceed with our original proposal! no changes and no limits on feed back! we just kept at the and asking to explain the reasons for all limitations until they really couldn't answer why and they turned around and backed down on everything!!! perseverance!