Renewable energy is still science-fiction. Renewables technology is ready to go, and is working reliably in countries around the world. South Africa has some of the best renewable resources in the world as it has one of the highest and most stable solar radiations in the world.
1 Desktop HP Compaq Pro 6305 MT PC (ENERGY STAR) 2 Desktop HP Compaq Pro 6305 SFF PC (ENERGY STAR) 3 Desktop HP EliteDesk 800 G1 Tower Business PC (ENERGY STAR) 4 Desktop HP EliteDesk 800 G1 Small Form Factor Business PC (ENERGY STAR) 5 Desktop HP EliteDesk 800 G1 Ultra-slim Desktop Business PC (ENERGY STAR) 6 Desktop HP ProDesk 600 G1 Tower Business PC (ENERGY STAR)
More massive stars are hotter and brighter. Massive stars have more fuel to sustain their output, but their energy output or luminosity is roughly proportional to the fourth power of their mass. A star twice as massive as the sun will emit energy 2 x 2 x 2 x 2 or 16 times the rate of the sun. With only twice as much fuel to sustain it, the star will only shine 2/16 or 1/8 as long as the sun before running out of fuel. We might compare stars to people.