2. A wind turbine has the maximum power output at the rated speed of 12 m/s and a rotor diameter of 82 meters. The cut-in and cut-out speeds for this type of wind turbine are 4 m/s and 23 m/s, respectively. The table below shows the annual wind data near a potential site for setting up a wind farm using this type of wind turbine and the power coefficient of the wind turbine at the specific wind speed. The air density is 1.22 kg/m³. Power coefficient n Wind speed (m/s) 0 5 10 15 20 25 30 0.25 0.5 0.25 0.1 Hours 1190 3000 2400 1700 400 50 20 (a). What is the maximum power output of this wind turbine, assuming Betz limit? (b). What is the average power output if the wind turbine is installed at this site?. (c). What is the capacity factor of the wind turbine at this site? (d). If a wind farm consisting of 100 such wind turbines is built at the site, how much energy does this wind farm generate in a year (in the unit of kWh)? (e). Is this a good site for using this particular type of wind turbine?

A turbine model has the following characteristics: Effective power: 13, 6 kW; Rotor Diameter: 0.38 meters, Flow: 0.34 ms, Energy Jump: 26.5 J / Kg and 3 R.P.S. rotation It is desired to construct a geometrically similar 1.20 meter diameter turbine that provides a power on the 656 kW axis, we ask: to calculate and justify its answers: a) the specific rotation; b) the unit quantities (rotation, flow and power); c) the rotation, flow and power of the model (bi-unit quantities).

An inflow to a turbine with a discharge of 20 m³/s leads to a ration speed of 150 rpm. The blades inlet edges have an angle of 120° to the direction of whirl. The outer diameter of the runner is 1.5 m and the runner inlet width is 1.0 m. 5. (a) To plot the velocity triangle at the blade outlet edge. (b) Assume design operating conditions and no velocity of whirl at outlet, calculate the power delivered by the runner. (c) The elevation difference between the head race and the tail race is 23 m and the head available to the turbine is 20 m, what is the hydraulic efficiency of the turbine and overall efficiency? (d) If a model of 1/10 full scale is constructed to operate under a head of 10 m, what must be its speed, power, water consumption and overall efficiency to run under the similar conditions to the prototype?

1. A new town is being developed in a rural area of Costa Rica. Planners are projecting a population of about 2,000 people and a baseload electric energy demand for the town of 10MWe over the first 20 years. A nearby river flows from the rainforest region with a mean annual flow of 100m³/s. Over a 20 km distance upstream of the town site, the river has a change in elevation of 1,000 m. Seasonal variations in the river flow could be as large as a factor of ten above or below the mean flow. Is a hydro project using turbines with 80% efficiency feasible to meet the town's future energy needs? Discuss (2-3 sentences each) at least two associated impacts that planners also need to consider in the hydro project design.

Consider two identical wind turbines with a hub height of 40 m, one located in flat agricultural land and one located above a forest. What is the relative output power for the two turbines if the wind velocity is 10 m/s at a height of 100 m in both cases? Pagricultural/Pforest = ?

Hydro electric station is installed to utilise 30 ma/sec of water of a river at a head of 7.5 m. If 85% turbine efficiency can be counted on, (i) is it feasible to develop this power by two turbines with rpm not less than 50, the turbine having specific speed not greater than 540 rpm ? (ii) what type of runner will be used ? (iii) what is the diameter of runner if the speed ratio is 0.85? [(i) N = 156'5 rpm, .. yes (ii) Kaplan (iii) P25 m]

An electric utility decides to add 50 MW of wind generation to its system. If the individual units are to be rated at 2 MW in a 13-m/s wind at standard conditions and have efficiencies Cp = 0.32, ηm = 0.94, and ηg = 0.96, what is the required swept area of each rotor?