A new electric power plant has an efficiency of 37%. For every 100 barrels of oil needed to run the turbine, how many are essentially lost as waste heat (in barrels of oil) to the environment?

A 75 W light bulb is used for 12 hours a day. The electricity for this bulb comes from a natural gas fired power plant that operates with 49% efficiency. How much CO₂ is emitted per day to power this light bulb? Make a simple estimate of the CO2 emissions from the power plant, ignoring transmission losses. 0.0024 kg CO2/day Xx 0.0024 We mentioned earlier in the course that energy technologies in developing countries often have much lower efficacies than those in developed countries. Let's look at one example, lighting via kerosene lamps, which are common in developing countries but about 150x less effective than incandescent lightbulbs at turning energy into useful light. If a family wanted just one tenth of the light provided by the 75 W lightbulb, they'd need to consume 15x as much power, or 1125 W. If a family ran 1125 W worth of kerosene lamps for just 2 hours each day, how much CO2 would this emit? You may assume that kerosene produces the same emissions as gasoline. 3.00 kg…

every second at Yosemite park approximately 500m^3 of water falls a distance of 97m. what is the increase in entropy per second due to the falling water? Assume the mass of the suroundings is so great that its tempature and that of the water stays nearly constant at 20 degree celcius . Also assume a negligible amount of water evaporates.

3. How much energy is transferred from a diesel engine to the exhaust and cooling system by heat if it performs 750 J of work in each cycle with an efficiency of 30 %. Solution: