Energy Engineering - Energy Accounting and impact assessment methods

Full exam

Energy Accounting and Impact Assessment Methods Academic Year 2022 -2023 - Exam 1 – 19 -01 -2023 Question A (3 points) How secondary products of a generic multi -product system can be classified ? Provide some examples of each category . Question B (4 points) What is the physical meaning of technical coefficients and Leontief Inverse coefficients ? Express the analytical link between them based on the power series expansion. Problem A (8 points) A single region supply and use table for Italy is given (excel file, tab “Problem A”) . Let us consider a policy intervention aimed at increas ing renewable electricity production , implying a yearly investment for the construction of new power plants corresponding to 16 billion € of “G oods ” products , leading to a switch of 10% of the electricity produc ed by fossil fuels to renewables . It is requ ested to: 1. Calculate the total demand by product and the total activity by technology for the baseline system based on Leontief production model , selecting and justifying a technology assumption . (1 pt) 2. Derive the product -by-product Leontief matrix for the given system , and briefly discuss the meaning of elements in its first column . (1 pt) 3. Implement the policy shock above on the given system . Describe the analytical procedure to apply the shock and assess the relative % change in total products demand and total technologies activity . (4 pt) 4. Assess the prospective impact of the policy shock on CO2 emissions and Labor according to a Production -Based accounting principle . (2 pt) Problem B (10 points) Let us consider a steel production system composed of a coal mine, a power plant, and a steel furnace . The steel furnace consumes 1.05 tons of coal and 200 kWh of electricity per ton of steel produced as output. The steel furnace also requires 0.5 cubic meters of water from the environment, and it causes 2000 kg of carbon dioxide emissions per ton of steel produced . The cost of the steel furn ace , including consumption of fixed capital, wages and taxes, can be estimated as 30 €/ton of steel. The electricity consumed by the steel furnace is produced by the power plant , burning fossil fuels (different than coal) , and leading to 0.65 kg of CO2 emitted per kWh produced. Each year, 250 tons of steel are delivered for final use s. It is requested to: 1. Indicat e the number of intermediate technologies and environmental transactions of the system , and define the Industry -by-Industry Input -Output coefficients table . (3 pt) 2. Calculate the yearly direct consumption of water by the steel furnace and its yearly direct CO2 emissions . (1 pt) A n ew policy constraint is imposed by the national authority , imposing a target reduction of steel production systems CO2 emissions of 25% within the next year . Th e system is considering a partial replace ment of the steel furnace with an alternative electric -arc furnace (EAF). The new process would reduce the consumption of coal , and the related direct CO2 emissions per ton of steel produced , by 90 %, while it would increase by 2 5% the water consumption and by 3 times the consumption of electricity. Requiring higher -skilled labor, the cost of this second plant is higher than the traditional one, reaching 37€/ton of steel. 3. Define a Rectangular Choice of Technology model (RCOT) as a Linear Optimization model, by adding the new technology described above named "EAF steel" in the previously defined IOT , in com petition with the standard steel furnace technology . Set and briefly justify the objective function and all the constraints of the model. (4 pt) 4. Calculate the minimum fraction of steel produced by the new process (EAF steel) to achieve the requested policy target . In this new system setting, w hat is the relative increase in CO2 emissions by the power plant? (2 pt)