One measure of the efficiency of a generator or power plant that converts a fuel into heat and into electricity is the heat rate. The heat rate is the amount of energy used by an electrical generator or power plant to generate one kilowatthour (kWh) of electricity. The U.S. Energy Information Administration (EIA) expresses heat rates in British thermal units (Btu) per net kWh generated.
The Constitution specifically grants Congress its most important power â the authority to make laws. A bill, or proposed law, only becomes a law after both the House of Representatives and the Senate have approved it in the same form.
The Executive Branch. Article II of the United States Constitution created and empowered our executive branch of government. The United States president leads the executive branch, which also includes the president's advisors, the 15-member cabinet and all federal agencies. Our president serves as our chief executive, or commander-in-chief.