Sustainable Living - Power

Power

When needed, sustainable living requires the use of sustainable energy. This involves the use of power in such a way that fulfills the requirements of the present without compromising the requirements of the future. Or, in short, using power sources and in such a way that can be sustained infinitely. This means the energy source must be renewable, and must not harm the environment or the people working under it. The most commonly used renewable sources of energy are: biomass, water, geothermal, wind, and solar.

As mentioned under Shelter, some sustainable households may choose to produce their own renewable energy, while others may choose to purchase it through the grid from a power company that harnesses sustainable sources (also mentioned previously are the methods of metering the production and consumption of electricity in a household). Purchasing sustainable energy, however, may simply not be possible in some locations due to its limited availability. 6 out of the 50 states in the US do not offer green energy, for example. For those that do, its consumers typically buy a fixed amount or a percentage of their monthly consumption from a company of their choice and the bought green energy is fed into the entire national grid. Technically, in this case, the green energy is not being fed directly to the household that buys it. In this case, it is possible that the actual amount of green electricity that the buying household receives is a small fraction of their total incoming electricity. This may or may not depend on the amount being purchased. The purpose of buying green electricity is to support their utility’s effort in producing sustainable energy. Producing sustainable energy on an individual household or community basis is much more flexible, but can still be limited in the richness of the sources that the location may afford (some locations may not be rich in renewable energy sources while others may have an abundance of it).

When generating renewable energy and feeding it back into the grid (in participating countries such as the US and Germany), producing households are typically paid at least the full standard electricity rate by their utility and are also given separate renewable energy credits that they can then sell to their utility, additionally (utilities are interested in buying these renewable energy credits because it allows them to claim that they produce renewable energy). In some special cases, producing households may be paid up to four times the standard electricity rate, but this is not common.

Solar power harnesses the energy of the sun to make electricity. Two typical methods for converting solar energy into electricity are photo-voltaic cells that are organized into panels and concentrated solar power, which uses mirrors to concentrate sunlight to either heat a fluid that runs an electrical generator via a steam turbine or heat engine, or to simply cast onto photo-voltaic cells. The energy created by photo-voltaic cells is a direct current and has to be converted to alternating current before it can be used in a household. At this point, users can choose to either store this direct current in batteries for later use, or use an AC/DC inverter for immediate use. To get the best out of a solar panel, the angle of incidence of the sun should be between 20 and 50 degrees. Solar power via photo-voltaic cells are usually the most expensive method to harnessing renewable energy, but is falling in price as technology advances and public interest increases. It has the advantages of being portable, easy to use on an individual basis, readily available for government grants and incentives, and being flexible regarding location (though it is most efficient when used in hot, arid areas since they tend to be the most sunny). For those that are lucky, affordable rental schemes may be found. Concentrated solar power plants are typically used on more of a community scale rather than an individual household scale, because of the amount of energy they are able to harness but can be done on an individual scale with a parabolic reflector.

Solar thermal energy is harnessed by collecting direct heat from the sun. One of the most common ways that this method is used by households is through solar water heating. In a broad perspective, these systems involve well insulated tanks for storage and collectors, are either passive or active systems (active systems have pumps that continuously circulate water through the collectors and storage tank) and, in active systems, involve either directly heating the water that will be used or heating a non-freezing heat-transfer fluid that then heats the water that will be used. Passive systems are cheaper than active systems since they do not require a pumping system (instead, they take advantage of the natural movement of hot water rising above cold water to cycle the water being used through the collector and storage tank).

Other methods of harnessing solar power are solar space heating (for heating internal building spaces), solar drying (for drying wood chips, fruits, grains, etc.), solar cookers, solar distillers, and other passive solar technologies (simply, harnessing sunlight without any mechanical means).

Wind power is harnessed through turbines, set on tall towers (typically 20’ or 6m with 10‘ or 3m diameter blades for an individual household‘s needs) that power a generator that creates electricity. They typically require an average of wind speed of 9 mi/hr (14 km/hr) to be worth their investment (as prescribed by the US Department of Energy), and are capable of paying for themselves within their lifetimes. Wind turbines in urban areas usually need to be mounted at least 30’ (10m) in the air to receive enough wind and to be void of nearby obstructions (such as neighboring buildings). Mounting a wind turbine may also require permission from authorities. Wind turbines have been criticized for the noise they produce, their appearance, and the argument that they can affect the migratory patterns of birds (their blades obstruct passage in the sky). Wind turbines are much more feasible for those living in rural areas and are one of the most cost-effective forms of renewable energy per kilowatt, approaching the cost of fossil fuels, and have quick paybacks.

For those that have a body of water flowing at an adequate speed (or falling from an adequate height) on their property, hydroelectricity may be an option. On a large scale, hydroelectricity, in the form of dams, has adverse environmental and social impacts. When on a small scale, however, in the form of single turbines, hydroelectricity is very sustainable. Single water turbines or even a group of single turbines are not environmentally or socially disruptive. On an individual household basis, single turbines are the probably the only economically feasible route (but can have high paybacks and is one of the most efficient methods of renewable energy production). It is more common for an eco-village to use this method rather than a singular household.

Geothermal energy production involves harnessing the hot water or steam below the earth’s surface, in reservoirs, to produce energy. Because the hot water or steam that is used is reinjected back into the reservoir, this source is considered sustainable. However, those that plan on getting their electricity from this source should be aware that there is controversy over the lifespan of each geothermal reservoir as some believe that their lifespans are naturally limited (they cool down over time, making geothermal energy production there eventually impossible). This method is often large scale as the system required to harness geothermal energy can be complex and requires deep drilling equipment. There do exist small individual scale geothermal operations, however, which harness reservoirs very close to the Earth’s surface, avoiding the need for extensive drilling and sometimes even taking advantage of lakes or ponds where there is already a depression. In this case, the heat is captured and sent to a geothermal heat pump system located inside the shelter or facility that needs it (oftentimes, this heat is used directly to warm a greenhouse during the colder months). Although geothermal energy is available everywhere on Earth, practicality and cost-effectiveness varies, directly related to the depth required to reach reservoirs. Places such as the Philippines, Hawaii, Alaska, Iceland, California, and Nevada have geothermal reservoirs closer to the Earth’s surface, making its production cost-effective.

Biomass power is created when any biological matter is burned as fuel. As with the case of using green materials in a household, it is best to use as much locally available material as possible so as to reduce the carbon footprint created by transportation. Although burning biomass for fuel releases carbon dioxide, sulfur compounds, and nitrogen compounds into the atmosphere, a major concern in a sustainable lifestyle, the amount that is released is sustainable (it will not contribute to a rise in carbon dioxide levels in the atmosphere). This is because the biological matter that is being burned releases the same amount of carbon dioxide that it consumed during its lifetime. However, burning biodiesel and bioethanol (see biofuel) when created from virgin material, is increasingly controversial and may or may not be considered sustainable because it inadvertently increases global poverty, the clearing of more land for new agriculture fields (the source of the biofuel is also the same source of food), and may use unsustainable growing methods (such as the use of environmentally harmful pesticides and fertilizers).

Read more about this topic:  Sustainable Living

Famous quotes containing the word power:

    His nature is too noble for the world;
    He would not flatter Neptune for his trident,
    Or Jove for’s power to thunder.
    William Shakespeare (1564–1616)

    In Europe, charters of liberty have been granted by Power. In America ... charters of power [are] granted by liberty.
    James Madison (1751–1836)

    What is genius—but the power of expressing a new individuality?
    Elizabeth Barrett Browning (1806–1861)