Nope, 1000 W per m^2 at normal incidence is all there is to it. Per square centimeter that's 1000/(100*100) = 0.1 W, so as the wiki you quote says (quite clearly I would have thought) you need 2300 times that, which you can obtain e.g. by focussing sunlight with a concentration factor of 2300:1, to get 230W on a square centimeter...
Michel ----- Original Message ----- From: "Brian Prothro" <[EMAIL PROTECTED]> To: <[email protected]> Sent: Wednesday, July 16, 2008 2:02 AM Subject: RE: [Vo]:Re: 70% solar panels > Now in my meager understandings in this area, I thought the 1000watts per > square meter is defined as a narrow "1 nm bandwith" of sunlight and is "a > measuring standard" not the full power falling on the surface of the Earth. > (The bands defined from below 400nm to 1700nm.) > > > > The test measurement is partially described as; > > "The ASTM G173 spectra represent terrestrial solar spectral irradiance on a > surface of specified orientation under one and only one set of specifed > atmospheric conditions. These distributions of power (watts per square meter > per nanometer of bandwidth) as a function of wavelength provide a single > common reference for evaluating spectrally selective PV materials with > respect to performance measured under varying natural and artifical sources > of light with various spectral distributions..." > > " > > > > So, if a panel absorbs multiple bands and is more efficient, as DBK seem to > have resolved thru engineering, then there is more power. I also saw > mentioned they work well in low light? (might be poor rcall on my part.) > > > > Now I am not an expert here, but the wiki says the power per square > centimeter is 230 watts: > > "One sun" is a measurement equal to the solar power incident at noon on a > clear summer day. I.e. in a 2300 sun system, approximately 230 watts per > square centimeter are concentrated onto the cell system.[14] > > > > Does the Additional multiple junction solar technology not tend to be far > higher in production that the normal 15%? DBK claims Five levels. > > > > I will ask DBK this directly... > > > > FYI -here is a chart of all current peak outputs for various technologies > for solar cells > > http://en.wikipedia.org/wiki/Image:PVeff%28rev110707%29d.jpg > > > > Brian Prothro > > > > > > -----Original Message----- > From: Michel Jullian [mailto:[EMAIL PROTECTED] > Sent: Tuesday, July 15, 2008 5:41 PM > To: [email protected] > Subject: [Vo]:Re: 70% solar panels > > > > 1/ Making use of 70% of wavelengths doesn't mean 70% efficient! > > > > 2/ From the details you provide it seems that the panel has an embarked > battery, which is fed by the ~200 W solar cells, and which is feeding a 3kW > inverter. This allows them to claim 3kW for the panel, which indeed it can > provide, but of course not more than 200/3000 = 7% of the full insolation > time as they conveniently forget to specify. > > > > They probably hope some people will be gullible enough to believe it can > provide 3kW full time, while receiving only 1.3kW solar irradiation! > > > > I see no reason why the product can't be a good one BTW, apart from the > misleading way in which they present it. > > > > Michel > >
