Eco/304 Week 2 Essay

Elaine Vieira
Week 2 iLab –
Exercise 1 * Compare/contrast commercial wind turbines "offshore" versus "on land". Land wind turbines “on-shore” are installed in land-based applications, while “off-shore” wind turbines are installed over water. There are some advantages and drawbacks; such as the environmental impact of offshore wind is considerably reduced compared with those onshore; although noise and visual impact are questionable to be problems there are some concerns. For example, there could be an environmental impact such as localized disturbance of the seabed from the noise caused by the turbine underwater. Another fact are that off-shore turbines tend to have larger ratings, because the cost of installation is greater, according
to estimates based partly on European experience since 1991, offshore wind energy costs are around 30-50% higher than onshore, due to larger machine size and the costs of transporting and installing at sea. However, these prices are expected to drop as happened onshore as technology improves and more experience is gained. According to studies in Denmark wind resources with the key factor being water depth are currently considered economically reasonable up to 40 kilometers from shore. Also winds tend to be steadier in off-shore applications, so larger turbines will generate more power, and helps predict payback period and shorten it. A drawback about offshore is although many people, while agreeing that wind turbines are a useful strategy, are not happy to see them in their area because they do not like the looks of the ocean shoreline being filled with turbines. The technology is well developed but off-shore wind is expensive because of construction costs and bringing the power to grid. And also might be difficult to maintain the windmills out at sea.

* Compare the electricity created from a home wind turbine versus a home wind "spire".
Wind spire, spins around a vertical axis, it can catch the wind from any direction to turn the rotor without re-orienting itself. The airfoils also spin more slowly than the tips of propeller style blades, rendering it virtually silent. Wind spire was specially designed with aesthetics and minimal cost in mind, around $ 5,000. Wind spire will produce approximately 2000 kilowatt hours per year in 12 mile per hour average winds, size: 30 ft. tall, 2 ft. wide.
Wind turbine, collects kinetic energy from the wind and converts it to electricity that is compatible with a home’s electrical system. Homes are served by both the wind turbine and the local utility. Wind speeds must be 10 mph or higher. As the wind increases, turbine output increases and the amount of power purchased from the utility is proportionately decreased. When the turbine produces more power than the house needs, the extra electricity is sold to the local utility. This is done automatically. Usually homes use about 9,400 kilowatt-hours of electricity per year; a wind turbine rated in the 5 to 15 kilowatt range would be required to meet the demand.

* How many wind spires would your home (or use an average 2000 square foot home)? Need to cover your daily electrical needs? (Cite your references.)
The number of wind spire that would be used in a house of 2000sf.
is not known per square foot average, as the cost of a system in fact depends on know how much energy (kilowatt-hours, kWh) the owners you use daily, how many full sun hours you receive per day; and if you have other sources of electricity. Another fact is that depending on wind speeds in a particular area, a homeowner may install two or three systems to generate 100 percent of the required power. As an example one homeowner in Nevada installed a single Wind spire to generate about 25 percent of his home’s power supply. Each Wind spire will generate approximately 2,000 kWh a year based on 11 mph average annual wind speed.
According to monthly average graphic below provided by AltE Store these examples represent only a small sample of possible combinations of electricity usage for households, to demonstrate the amount of PV it will take. To power the need depends upon electricity use and NOT the square footage of your home. Some examples of household usage | Solar Electric Info | | Square Footage | Electrical usage (kwh) | average kwh/ square foot | # of watts of PV to cover 100% of electricity usage | Watts PV/ Square Foot | Main heating source | 1000 | 377 | .377 | 2200 | 2.2 | Oil | 1270 | 250 | .197 | 1500 | 1.1 | Gas | 1800 | 250 | .139 | 1500 | 1.1 | Propane | 2000 | 295 | .148 | 1700 | 0.9 | Oil | 2650 | 1175 | .44 | 6900 | 2.9 | Oil | 2800 | 1010 | .36 | 5900 | 2.1 | Oil/wood | 3000 |
1555 | .518 | 9100 | 3 | Gas/wood |

Exercise 2 * Geothermal heat is having another "revival". Explain how it works in a home and how much it would cost to add this to your home (determines your square footage or use an average 2000 square foot home)? Cite your references. Due to the rising cost of energy and oil Geothermal is having another revival.
Geothermal heat pump doesn 't create heat by burning fuel, like a furnace does. Heating utilizes the natural temperature of the ground at about 10 feet and below which averages about 68 degrees Fahrenheit. In winter it collects the Earth 's natural heat through a series of pipes, called a loop, installed below the surface of the ground or submersed in a pond or lake. Fluid circulates through the loop and carries the heat to the house where an electrically driven compressor and a heat exchanger concentrate the Earth 's energy and release it inside the home at a higher temperature. Ductwork distributes the heat to different rooms. In summer, the process is inverted. The underground loop draws excess heat from the house and allows it to be absorbed by the Earth. The system cools your home in the same way that a refrigerator keeps your food cool, by drawing heat from the interior, not by blowing in cold
air. The geothermal loop that is buried underground , trenches are dug or holes are drilled and plastic tubing made of high-density polyethylene, a hard plastic that is very durable but which permits heat to pass through efficiently is placed in them. Tubing is then filled with a circulating fluid, usually just water or an environmentally safe antifreeze solution that circulates through the pipes in a closed system, and heated to the temperature of the ground during circulation. The fluid then goes to a heat exchanger where the heat of the fluid is exchanged to the air, which in turn circulates through the house to warm it. When installers connect sections of pipe, they heat fuse the joints, making the connections stronger than the pipe itself. This eliminates the need for a compressor in a heat pump, which uses a lot of energy to compress a substance like refrigerants into a liquid. On average, a geothermal heat pump saves about 7 out of ten energy units that would go into operating a standard heat pump. The main additional cost of adding a geothermal heat pump is in the installation of the tubing in the trenches or holes, which can be expensive because it requires special machinery like a large excavator or drill rig. The average added cost is about $5K-10K, but can be paid back within a few years depending on energy costs in your area. Additional type of geothermal system uses a loop of copper piping placed underground. When refrigerant is pumped through the loop, heat is transferred directly through the copper to the earth.

* How much would it cost to install enough solar panels on your roof to generate all your daily electrical needs? How many panels (size?) would you need? To calculate how many square inches of solar panel I need for my house, I need to know: how much power the house consumes on average, where the house is located that way I can calculate mean solar days, average rainfall, and so on. I 'll assume that on an average day the solar panels generate their maximum power for 5 hours. A "typical home" in America can use either electricity or gas to provide heat -- heat for the house, the hot water, the clothes dryer and the stove/oven. If you were to power a house with solar electricity, you would certainly use gas appliances because solar electricity is so expensive. This means that what you would be powering with solar electricity are things like the refrigerator, the lights, the computer, the TV, stereo equipment, motors in things like furnace fans and the washer, etc. Let 's say that all of those things average out to 600 watts on average. Over the course of 24 hours, you need 600 watts * 24 hours = 14,400 watt-hours per day.
From our calculations and assumptions above, we know that a solar panel can generate 70 milliwatts per square inch * 5 hours = 350 milliwatt hours per day. Therefore you need about 41,000 square inches of solar panel for the house. That 's a solar panel that measures about 285 square feet (about 26 square meters). That would cost around $16,000 right now. Then, because the sun only shines part of the time, you would need to purchase a battery bank, an inverter, and that often doubles the cost of the installation

* How can landscaping (trees/bushes) affect your heating and cooling bills? Landscaping made of trees, vines and shrubs can be used to shade your home and reduce your energy bills. Trees or shrubs can also be planted to shade air conditioning units, but they should not block the airflow. According to an estimation made by The U.S. Department of Energy just three trees, properly placed around the house, can save an average household between $100 and $250 in energy costs annually. To be most effective, trees should be strategically located on the south and west sides of your home. Deciduous trees are best, because they shade in summer and allow light and radiant heat to pass through in the winter. Choose deciduous trees native to your environment, fast growing and tall enough to be effective. Vines provide shading and cooling, and are quick to grow. Trellises should be placed on the hottest side of the house, and blocked out at least 6" from the wall to protect the wall and provide a buffer of cool air. Shrubs protect the lower portions of walls from heat gain by blocking sunlight. They also act as a windbreak in winter to help protect the house from cold air. Choose shrubs which are low maintenance and grow to a fixed height. Take care to locate trees or large bushes where their roots will be clear of underground wires, sewer lines or septic tanks, or the house foundation. Rock walls, paved areas and rock features should be kept to a minimum on south and west sides of the home, because they increase temperatures by radiating heat.

Exercise 3 * Choose any three cars brands that are a minivan, a compact car, and a sedan/crossover. Compare their mileage (city versus highway). Do any of these models come as a hybrid? If not choose one that does. Compare the fuel statistics for the same car as a "regular" gasoline car and the hybrid version. In your budget and life style, explain the fuel savings if your next car purchase was a hybrid vehicle. Include all references used.

Make and Model | Mpg | City | Highway | | | | | Honda Civic Hybrid | 40 | 28 | 50 | Honda Civic LX | 30 | 19 | 47 | Honda Accord LX | 25 | 17 | 37 | Toyota Sienna LE | 20 | 14 | 20 |

Hybrid vehicle has higher fuel efficiency that can save me sufficient amount of money over the years, that I can use the saving for my vacation.

References: http://www.oceanenergycouncil.com/index.php/Offshore-Wind/Offshore-Wind-Energy.html American Wind Energy Association. Resources. Wind Energy Basics.http://www.awea.org/faq/wwt_basics.html
"The Physics Fact book". http://hypertext book.com/facts/2003/BoiLu.shtml. Retrieved on 17 February 2009.
Wind Resources of Ohio. http://ohiowind.org/pdfs/OH_spd100m.pdf http://eartheasy.com/live_naturalcooling.htm http://www.consumersearch.com/station-wagons