3 Heating by computer The university campus uses a CHP plant, based on gas engines fuelled with natural gas. What is the CO2 emission per kWh electricity? Allocate based on exergy. Use the following data: a) Assume hot water is produced at 120C (pressurized). After heating the buildings. the water is returned to the CHP plant at 80C. Find typical values for electric and thermal efficiency of a gas-engine CHP plant in your book. b) A student suggests leaving the computers on, even if nobody uses them. The electricity used is turned into heat, so we reduce the amount of heat we need to produce. Is this student wrong, if we allocate the fuel use based on energy? Assume both heat and electricity is produced with the gas engine CHP plant. Explain your answer by carrying out an allocation analysis for the old (reference) situation in which the computers are turned off and new situation in which, the computers are left on. Call x the amount of electricity consumed by the computer c) Is the student wrong