|Główna » Artykuły » Moje artykuły|
Humans cannot sustain the path we've been taking with our consumption of resources and global population expected to peak at 9 billion by 2050. We need to learn how to live differently without decreasing our quality of life. One such possibility is to move towards a renewable energy economy. The following are the diverse types of renewable energy.
Biomass is when humans burn vegetation as a fuel source. Many argue that this not a viable option for human energy consumption. Burning biomass releases large amounts of carbon dioxide into the atmosphere and requires the destruction of ecosystems such as deforestation. There has also been a recent push for ethanol as a "green" source of energy. In the United States, corn has been used and subsidized to make ethanol. The effects have been a spiraling rising in the cost of corn-based food. Plus many would argue that humans should not be using food for fuel when humans are now consuming more food than we are producing. In Brazil, they are using sugarcane to produce ethanol. Because there is a lot of money to be made in the ethanol industry, Brazil is cutting down the Amazon rainforest to produce more sugarcane for their energy economy. So it can be argued that ethanol is not really a "green" energy if it requires deforesting the rain forests along with causing food prices to rise.
Hydroelectric power is also questionable as an energy source even though it is renewable. Hydroelectric power requires dams being built in order for flowing water to turn turbines within the dam to generate electricity. Their are numerous problems with power coming from hydroelectric dams. It requires flooding usable and often time fertile land to create a lake. Over time, the lake can fill up as sediment gets deposited into the lake. Dams can also harm aquatic wildlife such as salmon because the prevent them from returning to their spawning locations. In fact, many northwestern states in American have dismantled damns because salmon are near extinction. But it must be said that it is "clean" energy in that hydroelectric power does not pollute the air or water.
WIND POWER AND GEOTHERMAL ENERGY
Windmills have been around for hundreds of years, but only recently have they been used to generate electricity. Until last year, wind power was the fastest growing energy source in the world. And with the rising costs of fossil fuels, wind power is now cheaper to produce than energy from fossil fuels. Farmers are getting onboard with wind power because power companies will rent space to place the windmills, which will provide a steady income for the farmer. But the farmer can still grow their crops or have their cattle and maintain their way of life. Energy created by wind is similar to dams because the wind turns the blades, which turns a turbine within the windmill to generate electricity.
There are a few concerns with wind power though. Some do not like how windmills look because they require being out in the open; whereas coal power plants are easier to hide behind mountains. There is also concern that windmills, can harm migratory birds and bats. But wildlife is more likely to be hurt by changing climates than by small-scale windmills. Now out in Europe, they have been real serious about wind power. Some of the windmills along the continental shelf - where the winds are steadily consistent - have windmills so large you can land a helicopter on them. They are so large that each blade is over 300 feet long (said another way, each blade is taller than the Statue of Liberty). The United States is still far behind other countries in Europe, but that is starting to change. It is now possible to purchase wind power from various energy companies. The largest wind power program in the United States is called the Blue Skies Program by Rocky Mountain Power.
With the sun still having 5 billion years of life in it, our star is the ultimate renewable energy source. There is actually two types of solar energy: passive and active. Passive solar energy requires no special devices, rather south-facing windows and dark surfaces to light and heat buildings. This is a very inexpensive alternative, and it is surprising that it is not used more often. Active solar energy captures heat and generates electricity by using photovoltaic cells with solar panels. The panel's cells are made from silicon which is the second most abundant mineral on Earth's crust and when combined with other materials become sensitive to sunlight - called the photovoltaic effect. The electrons within the cells move through the silicon and produce an electrical current. In 2008 solar panels surpassed windmills as the fastest growing energy source in the world.
As you probably noticed with the different types of renewable energy, most require turning a turbine to generate electricity. Renewable energy is being used to supply electricity into the grid system for all the appliances that require electricity. Another use of renewable energy is for water heaters which require vast amounts of energy. In less developed nations, renewable energy such as solar panels is being used to provide electricity to people who are not connected to a grid system. There is also a new movement to include solar panels to the tops of hybrids and electric cars. In 2009, the new Toyota Prius will have an upgrade option to have solar panels on the top to charge the battery.
There has also been a steady demand to recycle rather than through products into our landfills. But recycling is not only about saving landfill space, it's about water, natural resources and energy. It requires a lot less energy, water, and resources from the earth to re-create something than to mine and process the raw material. Take a soda can. How long do you keep a soda can once you open it? Did you know that it may take up to three years for the material to be mined from the mountain, processed, shipped, filled with soda, and shipped to you? That is a lot of power, yet if you recycle products then there is more savings than just landfill space.
There is now a variety of ways someone can recycle. Many cities around the nation have curb-side recycling much like your garbage cans. There are also several drop-off sites, which are often found at retail and grocery stores. Buy-back centers are commercial businesses that purchase your recyclable goods. But it is important to note that what you can recycle for each can vary - so don't think you can dump anything you want into a recycling can just because you see one.
So once you recycle something, where does it go? There are four major manufacturing sectors that account for over half of the world's recycled products - paper mills, plastic converters, steel mills, and iron factories. The easiest items to make from recycled material is newspaper, paper towels, aluminum cans, steel, and glass. The problem with recycling comes with plastics because there are so many different types, and they can't be mixed in the recycling process. Many of you are aware that, at the bottom of plastic containers, there is a number from 1-7; these are different types of plastics. But you cannot recycle plastics of various types; they must be sorted out. If a #5 is mixed within a batch of #2 plastics, the entire batch is ruined. So make sure you are conscious of what you are doing when you recycle. Now some recycling companies have the ability to sort through the different types of plastics; so check with your recycling company if you are not sure which plastics you can recycle.
Open Geography Education by R. Adam Dastrup is licensed under a Creative Commons Attribution 4.0 International License
|Wyświetleń: 31 | Rating: 0.0/0|
|Liczba wszystkich komentarzy: 0|