Abstract

To Render a Household Independent of the Electrical Grid using a Micro Wind Turbine

Eoin RobinsonDepartment of Mechanical Engineering , Institute of Technology Tallaght Dublin , Tallaght ,Dublin 24

Energy Charts From the spreadsheet above it is clear that 12.43 Kilowatts will be required daily for the summer and 17.32 Kilowatts for the winter. This is at a cost of 127 € in the summer and 184€ in the winter per bi month with the current energy supplier Electric Ireland. An extra 30% will be added to the energy to cover losses, raising the total daily energy demand to 16.16 kW and 22.516 KW for summer and winter respectively. With the number of appliances reduced (see fig) the demand peaks at 8.1 KW at 6:00 p.m.It seems unrealistic to demand 16.61 KW a day for the urban home because the turbine diameter that can be expected at the urban home will be maximum of 2.0 m. the reason being that a larger diameter would be heavier meaning more noise as well as a higher tower so to allow the blades space to spin without hitting anything. Even 2.0m itself is large considering that it will most likely be in an back garden area where space is at a premium. The higher load

Energy Cost Chart The electrical grid supplies power to most households in Ireland. Electric Ireland (formerly the ESB) holds 57% of the domestic market followed by Airtricity (27%) and Bord Gais (18%). (McCárthaigh, 2012 ) . The task of this report will be an analysis of the cost of electrical power and to assess whether it is more cost effective to be independent of the electrical grid using a wind turbine to satisfy electrical power, and in the process eliminating the Standing charge. The standing charge is a tariff applied to all customers who utilize electricity in their homes/businesses. Electric Ireland owns the distribution and transport networks the standing charge is a fee paid exclusively to them.

 • To produce spreadsheets showing the energy usage of an

average urban and rural household.• To create a series of graphs which illustrate the time periods of

the highest energy usage in a typical household.• Analyze the various appliances and assess which can be

switched from electrical supply to an alternate energy supply. Also giving the relevant costs associated with substitutes.

• Gather information on turbines suitable for urban and rural homesteads

• Select the turbines based on a design specification.• Calculate the cost benefits and payback period of each

turbine.• Conclude whether it is/not cost effective for a household to

become totally independent of the electrical supply using a small wind turbine.

 

Conclusion

Wind Patterns in Ireland. Windspeed will be affected by a number of factors, obstacles such as trees, building structures and mountainous terrain. ‘Ireland’s east coast is quite windy with speeds ranging from 7 – 18 m.p.h. while its northern and western coast experiences extremely windy weather with Gale force winds on average of 50 times per year. These windspeeds have made Ireland’s north and west coasts two of the windiest coasts in Europe’ (MetEireann, 2012). The chart below illustrates the average windspeeds occurring in each area. Knowinf the avergae wind velocities in an area is vital to gauging how much wind can be harness by the micro wind turbines.

Urban The urban turbine has a restriction by law of 6m rotor diameter. There must be a clearance of at least 3 meter above any object. Because urban households have higher restrictions placed upon them it is unlikely that an urban household will have a wind turbine diameter greater than 2.5 meters will be accepted. Anything over 3m would be too large for an urban back garden of 25 m 2. Urban wind turbines will have to be lighter so as to not create too much noise that may annoy neighbors.  Lifetime for most wind turbines is 20 – 25 years, however a constraint of 10 years will be inputted. If no unit can satisfy this parameter then the closest to it will receive higher points in the scoring. Since the average windspeed around Dublin is 5.6 m/s , the turbines with the most power generation capability at this speed should be targeted. Design analysis will now split up into 2 sections Rural and Urban. This will also cut down costs. The 3 turbines above will scored against each other based upon design criteria and the unit which satisfies the most criteria was the winner. The two turbines above were selected for urban and rural households respectively.

Project Aims

Renewable EnergyRenewable energy will be of major importance for Ireland in the coming years. Given its lack of fossil fuels and its fantastic wind resources it likely that windpower will be at the forefront of the renewable energy resource production. ’Large-scale windElectricity generation reached 1264 MW installed capacity by 2010 in the Rep of Ireland’ .Given the unknown economics of running a small scale wind turbine wind generation for urban and rural households is relatively unknown. The increased cost of fossil fuel the current swing towards green technological development and the changing government policies concerning climate change renders wind power in Ireland a dynamic concept. The energy demand in Ireland continues to rise. ’On average the annual electricity consumption load for a household in the Rep. Of Ireland was 5557 kWh in 2008’. This was mainly due to the increase number of appliances and power loads needed per household. Meaning that wind generator should be sized for increased potential loads in the coming years to be able any serious return on investment. This increase in load has had environmental implications.Small wind turbines can play a role to help Ireland meet its energy targets for 2015.  

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(Summer)Time vs Peak Usage (KWHr)

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rs Concept 1: Swift - Renewable Energy Devices –

Payback periodIn conclusion it is unlikely that a 15m high wind turbine would be tolerated small urban back garden. If it were it is clear from the financial analysis that the Swift turbine would generate positive wealth. However it would not be large enough to generate sufficient energy to satisfy all of the customers energy needs, even with demand significantly reduced. Thus the turbine would be placed in a supporting role for the house and not render it independent electrical grid. The Rural house should by all means install Windpower. Depending upon the site if the homeowner has a wide open space and few obstructions they should consider an installation. They would be under less legal restrictions to limit the size and with a 5m diameter turbine could service the entire homes energy needs.

This chart is an example of an urban household over the summer with a family of 5 living in it. 3 more charts were made for Winter, Rural summer and Rural Winter. The charts provide an estimate of energy usage in a typical house.A list of appliances was drawn up.The appliances were rated in KWHr . Each appliance was given a ‘number of hours on’ per day , then multiplied by the unit rate of the 3 main energy providers to give a cost per day per appliance.

The chart highlighted the high energy/cost devices in the household .The main electricity users were the shower, kettle , oven, washing machine and dryer.

This chart was compared against a similar household of 5 people , and set against there bill for accuracy. It proved to be 90% accurate .

Rural

This formula was used calculate the payback periods for the 2 turbines above .