The G83 form

[Triassic]

I’m on a rural supply fed via overhead cables on poles. I’d assumed I’d have to get prior permission to install solar panels, so I contacted the DNO who sent me form G83/2.   Having read the form it’s to be filled at the point the system is commissioned. Am I correct in assuming that anyone can connect solar panels to the distribution network without prior approval, the only requirement being you fill in and send the DNO the completed G83 form. 

 

Confused of Cumbria. !

[vivienz]

How much are you putting up?

[Stones]

@Triassic I looked into this a couple of years ago

 

 

[Triassic]

The DNO said If it is less than 3.68kW, then complete the G83 form. In reality I’m going to installl 4kW of panels. I assume the inverter limits the export to the grid.

 

ps. As this is a non FiT install is there anything else I need to be aware of? 

Edited September 5, 2018 by Triassic

[Jeremy Harris]

The short answer is that anyone can fit up to 16 A per phase of microgeneration, without the consent of the DNO.  Don't get confused by power - it doesn't, strictly speaking, apply, as the G83/2 limit is 16 A per phase and the power can vary a great deal depending on the supply voltage at any time.

 

For example, the official UK supply voltage is 230 VAC +10%, -6%.  It's a fudge, as the true UK supply voltage is the same as it was before unification with the EU, about 240 VAC, hence the offset tolerance.

 

16 A at 230 VAC = 3.68 kW, hence that figure being quoted.  But, at 240 VAC (which is a more realistic figure) the power will be 16 x 240 = 3.84 kW.  At the upper limit of the UK supply voltage, 253 VAC, the G83/2 power limit increases to 16 x 253 = 4.048 kW.  In the sloppy parlance used by PV installers, a G83/2 compliant system is very often called a 4 kW system, and as long as the inverter is set to limit to 16 A per phase (which just means selecting the G83/2 mode on it during installation) then you will be compliant if you have 16 off 250 W nominal panels, as the vast majority of UK G83/2 systems have.

[Ed Davies]

The legal bit: http://www.legislation.gov.uk/uksi/2002/2665/regulation/22/made

 

So, yes, if you've got a normal G83 (or G59) compliant system and you're not going to feed in more than 16 amps per phase then you just have to inform them when the system's commissioned.

 

AIUI the DNOs are happy if the inverter (or the panels) limit the power to no more than 3.68 kW even though this is slightly more than 16 amps if the voltage is below 230 V (a compliant supply can be down to 230 V - 6% = 216.2 V where it would be a tad over 17 amps). What they're worried about is if the line is already close to the upper limit (253 V) and somebody sticking an extra 16 amps takes it over that. If the voltage is sagging and you put a bit more current in you're doing them a favour.