Waste power plant efficiency math problem

AI Thread Summary
The discussion revolves around calculating the potential electrical energy production from burning 230 million tonnes of solid waste in waste-to-energy power plants with a 20% efficiency rate. Participants are tasked with determining the annual kilowatt-hours produced and comparing it to the total US electrical energy production of 3.8 trillion kWh. Additionally, they need to calculate the average electric power output from these plants and assess how many 1-GW coal-fired plants could be displaced. Key concepts include the conversion of tonnes to kilograms and understanding energy density, which is noted as 20 MJ/kg. The calculations aim to highlight the efficiency and potential impact of waste-to-energy systems on energy production.
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Homework Statement



If 230 million tonnes of solid waste were burned in waste-to-energy power plants that are 20% efficient

a) how many kilowatt- hours of electrical energy could be produced in a year? Compare this quantity with the total US electrical energy production of 3.8 trillion kWh annually

b) what would be the equivalent average electric power output from all those waste- burning power plants? How many 1- GW coal- fired plants could they displace?


Homework Equations





The Attempt at a Solution



For part A, I am not sure how to calculate kWh. I know that 1 tonne is equivalent to 1000 kg. I am not sure if this is relevant in any way.
 
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Also the energy density is 20 MJ/kg not sure what this means though
 

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