It is generally inexpensive compared to other sources. Active Solar vs. Passive Active uses machinery (pumps/fans); Passive does not. Hydrogen Fuel Cells
: Includes fossil fuels (coal, oil, natural gas) and uranium (nuclear). These exist in limited quantities and cannot be replaced within a human timeframe.
Generate electricity by reacting hydrogen with oxygen; byproduct is water.
Answer: c) Coal
It is generally inexpensive compared to other sources. Active Solar vs. Passive Active uses machinery (pumps/fans); Passive does not. Hydrogen Fuel Cells
: Includes fossil fuels (coal, oil, natural gas) and uranium (nuclear). These exist in limited quantities and cannot be replaced within a human timeframe.
Generate electricity by reacting hydrogen with oxygen; byproduct is water.
Answer: c) Coal