A. Condensation is not caused by double glazing (although new windows can sometimes make condensation problems worse, by cutting out draughts). Treatment for condensation is ventilation (to vent moisture-bearing air to the outside) and heating (to raise surfaces above dew point temperature).
A typical residential solar PV panel system in the U.S. costs $3.60/watt after installation, and the solar panels typically save the customer over $20,000 (net) over the course of 20 years. Learn more about the many advantages of solar energy. typical residential solar PV panel system in the U.S. costs $3.60/watt after installation, and the solar panels typically save the customer over $20,000 (net) over the course of 20 years. Learn more about the many advantages of solar energy.
At an installed price of $1.25 per watt, the cost of PV solar is always cheaper than coal. At $2 per watt, it is cheaper after year 40. At $3.00 per watt, it is cheaper about year 80. It is expected that PV solar costs will reach conventional coal parity by 2017.