Explain the terms biomass and bioenergy and the difference between them. [4 marks] (b) Discuss the benefits and challenges of bioenergy as a sustainable component of the global energy system. [6 marks) (c) An electricity grid system receives its generation from a combination of wind and solar photovoltaic (PV) with biomass power plants to balance the system (Table Q2.1). Total final consumption of electricity is 90 TWh, peak power consumption is 25 GW and transmission & distribution losses are 11%. Table Q2.1: Generation mix Generation type Capacity Capacity Factor Onshore wind 20 GW 29% Solar PV 11 GW 13% Biomass ? 70% (0) Calculate the necessary installed capacity of the biomass generators. (11) Calculate the minimum biomass primary energy required if the power plant efficiency is 32%. (iii) Explain why your answer to part (ll) is likely to be an underestimate of the total primary energy required to supply this biomass. (iv) Briefly describe demand side management and explain why it may be preferable to balancing this system with biomass power plants. Give your numerical answers to an appropriate number of significant figures. If coal has an emission factor of 0.8MtC/Mtoe, and the electricity grid is made up of 20% coal fired power stations, 50% nuclear power and 30% renewables, what is the approximate amount of CO2 released when 5 Mtoe of electricity is consumed in the household sector over 1 year? [5 marks] What is meant by a ‘renewable resource’ – briefly discuss [4 marks] If per capita emissions in Germany in the year 2000 wire 6.7 tonnes of carbon per person per year, and those in Malaysia were 0.8 tonnes of carbon per person per year, and both nations aimed for the same per capita emissions of 1 tonnes of carbon per person per year by 2050, starting in 2000, what would the annual constant percentage rate of change in per capita emissions be for Germany over the period? [4 marks]
