Do you need info for your Solar PV Development?

[Kevin Hard]

One of our friendly team will help answer your question.

[Will Gibbs]

Kev,

I have a project in Cambridgeshire. The client is interested in a whole range of renewable technologies and has no particular objective to save carbon, he is more interested in securing his energy supply. Can you give me the latest figures for PV efficiencies, price per kWpeak etc. What information do you have on the new type of hybrid PV?

[Kevin Hard]

Hi Will - good to see you on here.

The initial benchmark figures I'd use for PV output would be 780kWh/an for polycrystalline at 5k/kW and 830 kWh/an for mono at 5.7k/kW (costs based on standard bolt on roof fixing). Sunpower have the highest efficiency at the mo with outputs predicted at 890 kWh/an - I'd suggest going for the sunpower module or the monocrystalline panels if you have targets to hit and limited space. If you have the roof space, then poly is a more cost effective option.

Speak soon
Kev

[Will Gibbs]

Kev,

These figures quoted in kWh/an I presume are per kWp? What basis do manufacturers quote annual energy outputs for their panels, what are the conditions under which they're tested? Using our hourly data for solar position, angle of panel, orientation of panel and efficiency, I tend to get annual outputs in the UK above those manufacturers claim. I find this quite odd that manufacturers would quote lower figures than our calcs give (I have checked the calculations and I'm confident they are ok).

Hope you enjoyed Christmas and NY,

Will

[Kevin Hard]

Hi Will - Happy New Year.

You've got it - those are the estimated kWh per kWp.

Are you using the toolkit for your predicted outputs? I didn't have chance to modify it before i left. Basically it needs to include inverter and sytstem losses. It currently estimates irradiation for the area, orientation etc and then assumes a panel efficiency - does not include for system losses.

All manufacturers data is based on a standard test condition (Certified to IEC 61215) - this includes basing it on 1000W/m2 of irradiation. I think you would have a case for modifying your benchmark kWh's if you could estimate a greater level of irradiation - like the toolkit suggests.

Kev