I want to be made my evaluation part of my essay. I shoulde just 5 sentence.

 

“Renewable energy utilizes natural cycles and systems—such as sunlight, wind, tides, and geothermal heat—to harness natural energy.”

 

 

In the following viewpoint, the Environmental Literacy Council (ELC) argues that renewable energy sources—wind, solar, hydropower, geothermal, and biomass—can help fight climate change because they generally have fewer greenhouse gas emissions than fossil fuels. However, renewable energy sources do have some associated pollution and currently they are expensive. The ELC says further investment in research and development is needed to promote renewable energy. The Environmental Literary Council is a nonprofit organization that provides educational tools and resources on environmental issues.

 

As you read, consider the following questions:

1. According to the Environmental Literacy Council (ELC), what is the largest source of energy at the present time?
2. Which two renewable energy sources does the ELC say are intermittent?
3. According to the ELC, what is the main obstacle to using renewable energy sources?

 

There are many different types of renewable energy sources, including biomass, wind, solar, hydropower, and geothermal heat. Many of these sources have a long history of use, with one of the oldest forms, wood, having been used for heating and cooking by early [humans]. Biomass [e.g., wood, among other things] is still the largest renewable energy resource used today.

Renewable sources of energy dominated up until the 20th century when fossil fuels became the preferred source due to their low cost and convenience. While fossil fuels remain the largest source of energy, concern over climatechange, the rising cost of oil, and questions regarding fossil fuel supplies have increased interest in the production and use of renewable energy sources.

 

Renewable Energy Is Replenishable and Climate Friendly

 

Renewable energy utilizes natural cycles and systems—such as sunlight, wind, tides, and geothermal heat—to harness natural energy and create energy in a form ready for human consumption. Renewable energy sources differ from fossil fuels in that they can be replenished and their use produces little—if any—greenhouse gas [carbon dioxide]. Although most renewable energy sources do not produce greenhouse gases during energy production, they can consume a large amount of energy during their…construction and initial set-up. For example, it can take a wind turbine nearly 7 months of producing energy in order to offset its initial energy consumption and emission of greenhouse gases during its build. However, a wind turbine can typically produce over 30 times this amount of energy over the course of its lifetime. Therefore, although there are initial emissions in energy input, there is a net energy gain and greenhouse gas emission reduction from use.

Although relying solely on renewable energy would produce little greenhouse gas emissions, it is rarely feasible to do so. Some sources can be intermittent, such as solar and wind, requiring either use of a combination of energy sources or a form of energy storage. If the electric grid within the United States was powered only by renewable energy today, it would not be reliable. However, it is possible that with more research and development, renewable energy can become more reliable on a large scale basis.

 

Renewable Energy Combined with Fossil Fuels Is Optimal

 

The combination of fossil fuels and renewable energy has proven very successful—both at providing reliable power and at reducing overall greenhouse gas emissions. Biodiesel and ethanol, for example, can be combined with gasoline for cleaner transportation fuel. Sunlight can be combined with standard electric lighting to produce hybrid solar lighting, one of the newest developments in solar technology. Hydroelectric and wind power, used in conjunction with fossil fuels to produce electricity, can also reduce the amount of coal, natural gas and petroleumneeded.

China and Germany currently have the largest investment in renewable energy technologies, although the fastest growing group of countries in terms of usage is in Europe, where governments promote renewable energy industriesthrough tax incentives and subsidies. A number of countries have also developed renewable electricity standards, also known as renewable portfolio standards, which require electric service providers to gradually increase the amount of renewable energy sources used in their electricity supplies. In the U.S., nearly half the states and the District of Columbia have already developed such standards. Other countries include Australia, Japan, China, Italy, and the U.K. [United Kingdom].

 

Renewable Energy Obstacles and Criticisms

 

The main obstacle to using renewable energy sources is cost. While overall costs continue to decrease, most of the technologies remain more expensive than conventional fossil fuel technologies. However, much of the high cost stemming from renewable technologies is in the initial set-up, after which, operating costs tend to be lower than that of fossil fuel power plants. Some experts have suggested that if some of the costs associated with renewable energy were temporarily subsidized, it would help increase their production and capacity to produce energy.

While renewable energy technologies tend to be better for the environment, they also face additional criticisms. Although the majority of renewable energy sources do not directly emit pollution, the use of some materials in the production of renewable technologies, such as photovoltaic cells, generates both waste and pollution. Other sources require a large amount of land (harvesting for biomass, siting for wind or hydropower), which could be used for agricultural or other purposes, or left undeveloped. Hydro and wind power facilities can also have a negative impact on ecosystems, obstructing fish passage and bird migration, respectively.

Further investment in research and development is needed in order to continue to bring costs down and streamline renewable energy technologies to reduce their impact on the environment. However, renewable energy resources hold great potential for reducing the threat of climate change through decreased greenhouse gas emissions and, due to the fact that they can be replenished, could help alleviate the risk of exhausting the world’s fossil fuel supply.

• Chart: Renewable Energy Consumption in the Nation’s Energy Supply, 2005

please do not write complex sentences.