BMW Unveils the Solar Charging Carport of the Future 165
cartechboy (2660665) writes "The carport hasn't changed much over the years. Made out of wood, aluminum or steel, they are simple structures meant to cover your vehicle from the elements. BMW has just revealed a concept carport that takes these structures into the future. Made out of bamboo and carbon fiber, this concept carport features solar panels that harvest the sun's energy and use it to charge your BMW i-vehicle. "With the solar carport concept we opted for a holistic approach: not only is the vehicle itself sustainable, but so is its energy supply," explained Tom Allemann of BMW Designworks USA. "This is therefore an entirely new generation of carports that allows energy to be produced in a simple and transparent way. It renders the overarching theme of lightweight design both visible and palpable." The entire thing is quite beautiful, and could be the way to make not only charging your electric car sustainable, but also building your carport."
Math check (Score:5, Informative)
Double checked my math. More like 22 kwh, or 66 miles worth of electricity a day.
Re:Math check (Score:4, Informative)
My method is just fine, thank you very much. I happen to work at a german research center on solar energy.
The performance ratio takes all losses in consideration (cable, MPP, inverter, shadowing,...) and isn't dependent on either the area (which is 27m2 for this carport, BTW) or the efficiency (about 15% for this carport).
With the performance ratio, you can convert solar irradiance (in kWh/m2.year) directly into specific yield (in kWh/kWp.year).
This carport has 3.6kWp capacity, and seems to be developed by Solarwatt.
Re:Math check (Score:4, Informative)
Take a look at the units for solar irradiance and specific yield.
They are *not* the same.
The 20% cell efficiency (or anything between 0.05 and 0.44) is included in the conversion between m2 and kWp : e.g. you need 5m2 of PV modules at 20% for 1kWp.
Performance ratio and cell efficiency are different notions. Performance ratio can theoretically be higher than 100%.
http://www.photon.info/photon_... [photon.info]
Re:Math check (Score:4, Informative)
Sorry if I wasn't clear.
I don't need to assume *any* cell efficiency, since this information is irrelevant.
The only needed information to calculate the energy yield are :
*) Solar irradiance
*) Nominal power
*) Performance ratio
Two 3.6kWp pv installations will produce the same energy yield for a given performance ratio, independently of their cell efficiency (i.e. size).