I have recently Just come across PV module that’s marketed as 235Wp +7% to +12%
To me that’s a 251Wp module with 0-5% variation in output
At first I was thinking – perhaps this is just marketing hype – but on reflection I am not so sure it isn’t more significant …
The module rating ultimately effects what FIT band a completed system falls into
- An array of 16 of these modules – according to the manufacturer – is rated at 3.76kWp >>> the highest FIT tariff band
- An array of 16 of these modules – at 251kWp each – is rated at 4.016kWp >> a lower tariff band
Obviously the larger the system – the bigger the impact. And if this principle is acceptable … what’s to stop a manufacturer rating a module at +20% to +25%
2 comments
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Laurie Tennant says:
January 30, 2012 at 1:28 pm (UTC 0)
Perhaps it’s a question of design: well-oriented, a nameplate 4kW which is actually a lot more than that risks either exporting more than 16A/phase, or wasting power that a smaller invertor can’t handle. However, in an east-west situation 5-6kWp might make sense, if only the FiT would accept it.
Yet another example of a technical scheme thought up by pen-pushers.
Keep up the good work.
Peter Randall says:
February 3, 2012 at 10:08 am (UTC 0)
In Scotland if you model a properly configured system of 4.5kwp connected to an inverter with an output limited to 3.6kw/16A, the number of days in a year where power is limited is minimal, but over the twelve months the increase in output over 4kWp is worth while.
FITs should be based on declared net capacity. In this way we could compensate for geographic location (where roof space allows) giving all consumers a more level playing field.