Photovoltaics and energy

This is a link to the information I compiled on solar power through photovoltaics. The take home message is:

1. photovoltaic cells will not power the entire load of a typical lab building of this size.
2. PVs can and do have higher conversion efficiencies, but the effeciences I calculated are for typical low-cost, high-availability modules, and the building materials with integrated PV that are currently being manufactured are in the low end of 6-10% efficiency, this is expected to improve steadily for some time.
3. Energy is energy. I think in thinking about our entire building system it will be helpful to take a step back and think about what energy really means. Everything in the world contains potential or kinetic energy - energy which is stored or energy which is doing work. Some key relationships are:
energy=mass*c^2
force=mass*acceleration
work=force*distance
Power (Watt)=work/time=force*velocity

So when we are talking about energy and watts and such, I guess I'm just trying to say that all of the typical means of storing energy are wrapped up in this. Useful energies can be thought of as: heat, mechanical, electrical and I guess nuclear energy -for large scale purposes, using these principles we need to convert to a type of energy we can use. The photovoltaic is convenient because the photons in light move electrons to create an electric current which is exactly a type of energy we want - electricity, but steam and turbines and gravity and heat sinks are also energetic processes that we can use to release or store energy for different building systems since we are dealing with water, air, and ground in addition to light.

PV slides

A cheesy but really clear discussion of types potential/kinetic energy and how it is used for our needs (for kids -but I think the simplicity is helpful)