Question

Question 4 (15 Marks) A. Using the power law, calculate the wind speed at 30 m if the wind speed at 50 m is 8.5 m/s. Assume the surface roughness exponent of the site is a 0.1. (3 Marks) B. What is the performance behaviour of Lithium -ion battery interms of discharge current and depth of discharge? (3 Marks) C. Explain the origin and features of Earth's tidal resources? (3 Marks) D. The data for a proposed short rotation coppice biomass project based on a three year cycle are as follows: The coppice produces 25 dry tonnes of wood per hectare each harvest The energy input associated with the production of fertilisers, herbicides and equipment is 10 GJ per hectare for the three years The energy used in harvesting and transporting the wood each time is 20 GJ per hectare The energy content of the biomass material is assumed to be 15 GJ per dry tonne Calculate the net energy produced in this biomass scheme? What area of coppice would be needed to service a 1 MW power station under the above conditions? (6 Marks)

Answer 1

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