A solar hot water system receives 12.8kWh/day (4kWh/m2 on a 4m2 system with 80% efficiency).  How many litres of water will that heat up by 55 degrees (heat capacity of 4.18 J/K/g)?

Assume there are 1.1 million rooftop solar hot water systems, each with 4m² surface area, receiving 4kWh/m2/day and absorb 80% of the solar energy.  Averaged over the course of the day, how much  power (in MW) will this generate?

Same wall as question 2, but now with addition of insulation, the thermal conductivity has been reduced to 0.3W/m²K.  Now how much heat is flowing (10m², 20⁰C gradient)? Include the units

 A brick wall with an area of 10m² and a thermal conductivity of 5W/m²K is experiencing a temperature gradient of 20⁰C (hotter outside than inside).  How much heat will be flowing through the wall? Be sure to include the units.

Convection refers to movement of heat though a moving medium, while conduction refers to the flow of heat though a material

High Concentration solar PV tends to use: 

Deployment of Concentrating PV reached its peak in:

Concentrating solar thermal and concentrating photovoltaics are essential the same technology, both converting solar energy into electricity via the same pathway

When deciding between tracking and non-tracking systems, designers need to also consider:

Which of these systems requires the most land to minimise shading problems?