Wind Energy Ally Keefe, Dave Mccabe, Geoff Frazier, Ryan Whalen, Meghan Moroni, Jeb Stuart, Brianna Parke, Peter Virchick

General Info Wind constitutes less than 3% of US energy sources. Many say wind has the power to add more to US generating capacity than coal in the next 20 years. North Dakota, Kansas, and Texas alone have enough harnessable wind to meet national electricity needs.

History of Wind Power Wind power evolved from the use of simple, light devices driven by aerodynamic forces to heavier drag devices and finally to light, more efficient lifts. The sailboat is the earliest known use of wind power. The first windmills were made to automate the tasks of grain grinding and water pumping in Persia AD

Wind as Electricity The first use of a windmill to generate electricity was in Cleveland, Ohio in 1888 by Charles F. Brush. In 1891, Dane Poul la Cour made the first aerodynamically (low solidity, four bladed) designed system. By 1920, the la Cour system replaced all previous sail and fan systems.

Development of Wind Technology -During the 1920’s modified propellers were used to drive direct current generators. -Bulk Power Wind Energy was first made in Russia in 1931 (100kw Balaclava Wind Generator). -The largest bulk wind energy producer was the Smith-Putnam Machine (Installed in Vermont, 1941)

European and American Involvement After WWII European Countries developed wind systems further when fossil fuel shortages led to high energy costs. US wind involvement began after the 1973 oil embargo. Beginning of the US Federal Wind Energy Program.

The Mechanics of a Wind Turbine

Where Does the Wind Come From? The wind is a by-product of solar energy. Approximately 2% of the sun's energy reaching the earth is converted into wind energy. The surface of the earth heats and cools unevenly, creating atmospheric pressure zones that make air flow from high- to low- pressure areas.

Wind power is a measure of the energy available in the wind. It is a function of the cube (third power) of the wind speed. If the wind speed is doubled, power in the wind increases by a factor of eight (23). This relationship means that small differences in wind speed lead to large differences in power.

Equation Of Wind Power The amount of power available in the wind is determined by the equation: w = 1/2 r A v3 w is power, r is air density, A is the rotor area, and v is the wind speed. This equation states that the power is equal to one-half, times the air density, times the rotor area, times the cube of the wind speed. Air density varies according to elevation, temperature and weather fronts.

Vertical Axis Turbines Although vertical axis wind turbines have existed for centuries, they are not as common as their horizontal counterparts. The main reason for this is that they do not take advantage of the higher wind speeds at higher elevations above the ground as well as horizontal axis turbines.

Horizontal Axis Turbine This is the most common wind turbine design. In addition to being parallel to the ground, the axis of blade rotation is parallel to the wind flow. Some machines are designed to operate in an upwind mode, with the blades upwind of the tower. In this case, a tail vane is usually used to keep the blades facing into the wind. Other designs operate in a downwind mode so that the wind passes the tower before striking the blades.

Rotor- The hub and the blades together are referred to as the rotor. Wind turns the blades which turn the drive shaft. Shaft- Two different shafts turn the generator. One is used for low speeds while another is used in high speeds. Gear Box- Gears connect the high and low speed shafts and increase the rotational speeds from about rotations per minute to about rpm, the rotational speed required by most generators to produce power.

Generator- The generator is what converts the turning motion of a wind turbine's blades into electricity. Inside this component, coils of wire are rotated in a magnetic field to produce electricity. Different generator designs produce either alternating current (AC) or direct current (DC), and they are available in a large range of output power ratings. The generator's rating, or size, is dependent on the length of the wind turbine's blades because more energy is captured by longer blades. Controller- Turns the blades on at 8-16 mph and shuts them down around 65 to prevent any high wind damage. Tower- Tall tubular metal shaft. The taller the tower, the more power produced.

Pros of Wind Power

Wind power Units are quickly constructed. Wind generators are much smaller in size compared other types electrical generators. Small size allows wind power to be very versatile.

Wind power is a great compliment to a house with a preexisting photovoltaic system. Serves as a great backup system. Wind power gives off no harmful emissions into the environment.

It is a renewable resource. The more time spent researching makes each new wind turbine more efficient. Mass production of wind turbines drives down costs.

Downfalls To Wind Energy Aesthetics – “Not in my back yard.” Inefficient and unreliable Hazard to bird migration

Aesthetics Turbines are around 50ft high and can be seen for miles Wind Farms use up more space than any other form of power plant Access roads will follow the construction of a wind farm Houses too close to turbines will be disturbed by their noise

“Not In My Back Yard”

Inefficient & Unreliable It is not uncommon for turbines to be hit by lightning strikes. This can cause damage to the turbine, and also provoke forest fires. Propellers often fall off and are not repaired – example -> Altamont area of California Inefficient: 9,369 turbines only produce 1.7 % of Germany’s power No Wind = No Power

Some Stats on Contribution and Failure Failure Stats for Germany (2000) FAULT % TURBINES AFFECTED Loosening of parts Cause unknown Other causes High wind Grid failure Control system Icing Component failure---44 Lightning CountryMW windpowe r Wind output (GWh/y) Total output (TWh/y) Wind contributi on (%) Denmark Germany Japan UK USA

Hazard To Bird Migration Turbines and power lines and a danger to migrating birds Proof: - Wind Power Monthly stated that large numbers of several bird species protected by European Law have been killed by turbines (1994) Red Tail Hawks, Golden Eagles are killed each year by turbines - English nature stated that habitat loss, significant death to birds, and changes in migratory patterns are a result of wind farms

Sources Hinrichs, Kleinbach, Energy: Its Use and the Environment, 3 rd ed. Thomson Learning, Australia Nigel Barnes, “An Ill Wind – An Objection Against Windfarms in Ireland.”

What is the Cape Wind Project? Proposal for the first off shore wind farm in the United States 130 turbines (24 square miles) maximum output=420 megawatts

Where will it be? Horseshoe Shoal, Nantucket Sound, Massachusetts At least five miles off shore Strong, consistent winds and shallow water Close to electrical interconnections and away from shipping lanes and boating traffic

Pros of the Project Replaces 113 million tons of oil per year “Zero-emissions” Boost to Cape Cod’s economy ,000 new jobs for Cape Codders Does not require land May help with navigation and rescue

Cons of the Project Private take over of public land May alter public use and access Decrease in property values No regulatory process to govern project Potential hazard to wildlife Aesthetics of Cape Cod’s natural landscape may be interrupted

Who are the major stakeholders? 17 different government agencies United States Army Corps of Engineers (USACE) Massachusetts Environmental Protection Agency (MEPA) Clean Power Now The Alliance to Protect Nantucket Sound

United States Army Corps of Engineers Regulate water resources Seven Principles (2002) No regulatory framework or experience NEPA, EIS, and MEPA Public Interest Doctrine Scientific Monitoring Station

The Alliance vs. Clean Power Now Supporters: U.S. Coast Guard Walter Cronkite? Argument: help navigation turbines are too slow Horseshoe Shoal is shallow best location Supporters: The Kennedys Gov. Mitt Romney Argument: navigation hazard blades will kill birds interrupts whale migration there are other nearby options

Clean Power Now Protest outside of USACE meeting in Falmouth, MA Charley Cummings (representative of the Brown College Environmental Action Network) Over 300 supporters gathered in front of the State House!

The Alliance to Protect Nantucket Sound State Rep. Demetrius J. Atsalis and Sen. Robert O’Leary Susan Nickerson, Director of the Alliance Cliff Caroll of Wind Stop

Cape Wind’s Visual Simulations from Cotuit 6.0 miles off the coast

The Alliance’s Simulation from Cotuit

Websites to check out (The Alliance)