Question: (a)(i) Describe one advantage of using hydroelectric power plants over using coal-fired power plants.

Answer:

Question: (a)(ii) Describe one potential disadvantage of hydroelectric power plants.

Answer:

Question: (b)(i) Propose a different renewable resource to use that would be a realistic solution to generating electricity without using fossil fuels or hydroelectric power in a grassland ecosystem.

Answer: -Solar energy/PV cells

-Biomass burning/ethanol production

-Wind energy/wind turbines

Question: (b)(ii) Justify the solution proposed in (b)(i) by explaining a potential advantage of using a different renewable resource to generate electricity.

Answer:

Question:

Answer: Work: ($0.05 per kWh - $0.11 per kWh)/$0.11 per kWh×100=(−$0.06 per kWh)/$0.11 per kWh×100

Answer: -55%

There will be a 55% savings by switching to hydroelectric power.

Question: (d) In a typical coal-fired power plant, 2,460kWh of electricity can be produced per ton of coal burned. Calculate how many tons of coal would have to be burned in a typical coal-fired power plant to provide the electricity for a typical house in the United States for a year. Show your work.

Answer: Work: 1.09×104 kWh/1 year×1 ton of coal/2.46×103 kWh

Answer: The coal-fired power plant would need to burn 4.43 tons of coal per year

Question:

Answer: Work: 9x10 TWH/1 year x 1x10^9 kwh/1 TWH x 1 house/1.09 x 10^4 kwh/year

Answer: 8,260,000 houses