# DTWS equate wind farm proposal

DonaJose

Drivetrain wind solutions propose this location in Inverclyde, Scotland, for a new 10 turbine wind farm. The wind farm will be located at the coordinates 55.909929°, -4.710663°, and was selected out of a group of 6 possible locations as the most suitable. Several justifications for this will be discussed further in this article.

### Power Output

The power output of each wind turbine is determined by the equation P = KAv3T. A in this equation represents the rotor area of the turbine, K is a constant 3.2, T is the number of turbines, and v represents the wind speed at this location. Each location varied in wind speed, and each turbine varied in height and rotor diameter (hence area). The wind speed at location 2 is 8.84ms-1, and the rotor diameter is 120m for turbine type 2, the turbine is determined suitable for the wind farm after calculations were performed. The area for turbine 2 has a value of 11309.73m2. Plugging this into the above equation, we are given the following value in watts:

250011017 kWh = 250,011 MWh.

The closest substation to this wind farm was a convenient 1km away. As well as being close by, the substation, Devol Moor, is rated 400kV, meaning that it can supply this wind farm with a capacity of 100MW. The number of turbines was selected based on this, to give an appropriate capacity factor. 10 type 2 turbines provide a capacity factor of just over 25.

The selection process was based on the power per upfront cost of the farm. The costs considered were the price of all turbines, payment for distance to the substation, and the price of foundations. The power across the whole farm was divided by these costs added together, and the most significant power per cost value was with turbine 1 at location 2. However, turbine type 1 was unsuitable for this wind farm, as the average wind speed of this location exceeded the maximum wind speed for turbine type 1. Hence, turbine type 2 was selected.

Electricity will be sold for £70 per MWh. The annual revenue for this wind farm was therefore £17,500,770.

A loan will need to be taken out to cover initial costs, such as the price of turbines, foundation work, and getting power to the substation. The cost of 10 type 2 turbines accounts for £23,220,000. The cost of laying foundations is 25% of the turbines, coming to £5,805,000. The other initial cost is a one-time payment of £750,000 per km to the substation. As the substation is only 1km away, £750,000 is all that will need to be paid in this regard. The total amount of money required for a loan is £29,775,000. This should be paid back over 10 years at an interest rate of 1%. This leads to the cost over 10 years being £32,890,124. This will be paid out of the revenue in yearly instalments of £3,289,013.

Out of the yearly revenue, certain outgoing payments are required. The loan repayments are an expense for the first 10 years. Rent will take a value of 6% of revenue + £6000 for the first 12 years of the project, and 8% of revenue + £8000 for the remaining 13 years of the project. £3,000,000 is set aside each year to compensate households within 5km of the wind farm. 10% of the cost of turbines is set aside each year for maintenance. Taking this into account, over 25 years, the project is expected to generate £240,601,762.

### Environmental Impact

The land in the area around location2 is peaty podzol. This kind of soil is infertile and extremely acidic. This means it lacks most nutrients for plants to grow. Because of this, this area is not divided into any special areas of conservation or special protection areas. The nearest special area is far away from our wind farm. It would not affect the power output of our wind turbines. Around the wind farm, there are no tall trees and no grass with berries, birds or wildlife wouldn't want to stay in a place like this. So, only one point that we need to pay attention to is there may be some birds or bats will pass through this area. So, we plan to set the ultrasonic deterrent “boom boxes” to go drive these birds away from the wind farm. The price of an ultrasonic deterrent device with 20-100 kHz is £1100. We have 10 turbines, so the total price is £11000.

We decided to build the wind farm 5000 meters from the nearest town. Thus, there is enough distance to ensure that noise and shadow flicker is not disturbing the daily life of residents when the turbine is running. If there are some influences from the shadow, we can stop the turbine for a while until the sun moves in other directions. But we may lose about £1,460,000 if the stop time is about 2 hours. Safety is also an important aspect for us. There are few cases of nacelle fires every year, some turbine nacelle fires cannot be extinguished because of their height and are sometimes left to burn themselves out. To prevent this situation, we decided to build an automatic fire extinguishing system on the turbine to automatically detect a fire, shut down the turbine unit, and extinguish the fires. The cost of installation of fire suppression systems is about £23,000, so installation of all the wind turbines costs £230,000.

Besides, carbon emissions now are also a very important point. When we build the wind farm, we need to minimize carbon dioxide emissions as much as possible. The main reason is that when wind turbines work, it makes the soil decompose faster thus releasing more carbon dioxide. So, we plan to use rough grazing to increase photosynthesis to absorb the released carbon dioxide.

The main social impacts of the wind turbine come from the fact that the proposed location is very close to Port Glasgow. Proposing such a large-scale project so close to people’s homes could provide several social impacts, which we have aimed to minimize.

Building a wind farm could potentially decrease the value of house prices in the town, which is quite distressing for the residents. However, compensation for each of the residents will be provided, at around £3,000,000 in total.

The development of new technologies in a town can, in turn, boost the economy, providing both long term and short-term job opportunities in this fast-growing sector. In counties with installed wind power, historically, a median increase in income and employment of 0.2% to 0.4% can be seen. Moreover, providing training sessions for enthusiastic residents allows them to enter this continuously developing sector as a source of jobs. This will then boost the local economy.

This site could also be used as a tourist attraction, by providing tours of the wind farm and allowing visitors to get a first-hand point of view of the farm and wind turbines in general. Furthermore, exposure to new technology can allow those with reservations to become more comfortable with the idea of wind farms being built so closely.

Another problem may be shadow flicker, which can cause discomfort. To minimize any impacts, we have decided to turn off the turbine when the shadow is cast on the town. While this may reduce our profit, as mentioned before, the comfort of the town residents is the priority.

The aim is to mitigate any negative social impacts by having clear, open communication between the company and the town. This could be achieved by creating a website with contact details and a link to post any concerns that have arisen at any point.

### WAsP

Our wind farm is made up of 10 turbines (all of them are type 2) and is located in the centre of this region.

Location of the met mast:

X-coordinate: 393068.0 m

Y-coordinate: 6197377.0 m

The prevailing wind directions at this location are west and southwest. According to the basic rule and mean speed map, the layout presents a band distribution in the prevailing distribution.

The distances between each turbine and the met mast are strictly controlled by 5 km, which will reduce the uncertainty of extrapolating wind flow across the site.

Google Earth shows that there’s another wind farm located northwest of our wind farm. The shortest distance between one of our turbines and one of those is up to 1.5 km, which means the additional wakes and trigger payments can be reduced as possible. In addition, our wind farm is located near a farm tour and a farmhouse. However, the direct distances are 1.01 miles and 1.05 miles relatively. They meet the noise standard, which is a 1-km buffer considering a large number of our turbine layouts.

Excluding the place mentioned above, the area is very quiet and open without too many residents.

From the output table, the mean wind speed at turbine locations is 8.27 m/s. It is reasonable and practical since the max speed of Turbine 2 is 10 m/s.

 Variable Total Mean Min Max Total gross AEP [GWh] 160.257 16.026 15.678 16.37 Total net AEP [GWh] 153.172 15.317 15.053 15.754 Proportional wake loss [%] 4.42 - 1.8 5.99 Capacity factor [%] 50.8 - 47.7 49.9 Mean speed [m/s] - 8.45 8.31 8.58 Mean speed (wake-reduced) [m/s] - 8.27 8.14 8.41 Air density [kg/m^3] - 1.213 1.205 1.219 Power density [W/m^2] - 666 631 695 RIX [%] - - 0.1 2.7

Note: The simulated capacity factor is around 50%. It is uncommon in real life and thus cannot be a practical reference.

Considering:

• Technical losses
• Availability (WTG, BOP and Grid): 0.95-0.97
• Electrical losses (to connection point): 0.96-0.99
• WTG Performance: 0.96-0.99
• Environmental (icing and degradation): 0.97-0.99
• Curtailment (noise, shadow, grid): 0.97 - 1.00

Taking the middle-ish values of the above, we would get:

P50 = 153.172(net)*0.96(availability)*0.97(electrical)*0.97(WTG performance) *0.98(Environmental)*0.985(Curtailment) =133.554 GWh

There are ten 3.6 MW WTGs. Thus, our net capacity factor would be 133.554/ (8766*10*3.6/1000) =42.32%

### Summary

According to the calculation and simulation. The location is suitable and the design proves to be practical. We have a clear financial plan and look forward to getting our windfarm project running on track in the future. It is our company’s top priority to make efficient use of Scotland’s abundant coastal wind energy while ensuring that the lives of the surrounding residents are not affected.