Solar costs have reduced 18% for every doubling of capacity, Climate Progress reports, giving details of briefings by solar industry executives in Washington, including graphics from presentations by Tom Dinwoodie of Sunpower and Dan Shugar of Solaria. Utility plants were installed at $7 in 2007. The average this year is $3. In the 6 years it will take to build a new coal plant, solar PV will be cheaper. A nuclear plant takes an average of 13 years, a 1 GW PV plant one year.