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Renewable Energy 101

​Renewable energy is energy that is generated from natural resources that are continually replenished. Sources of renewable energy include the sun, wind, moving water, and heat. Renewable energy can replace more traditional sources of energy, such as fossil fuels or nuclear, in four main areas: electricity generation, water/space heating, motor fuels, and off-grid applications.

 

Why Is Renewable Energy Important?

Renewable energy sources can be replenished in a relatively short period of time, are not tied to volatile foreign energy market conditions, and have less environmental impact than traditional energy sources. They can reduce the need for transporting electricity through cables, poles, towers, etc. However, some of these sources cannot always stay “on,” which can reduce the availability to our customers.

A Renewable Portfolio Standard (RPS) is a regulation that requires the increased use of renewable energy. The area we serve has regulated standards that require these goals are met every year. The standards carefully balance the mix of renewable energy sources and traditionally generated electricity to ensure we can provide a reliable supply to our customers.

What Does this Mean for You?

This means you and future generations can enjoy plentiful energy resources, reliable energy and a cleaner environment. Focusing on renewable energy sources means that each individual has a greater opportunity to make a difference in our carbon footprint, which can translate to a more secure energy future and environmentally friendly future for all.

Energy from the Sun

The sun has produced energy (solar radiation) for billions of years. This energy can be converted into other forms of energy, such as electricity. Photovoltaic (PV) or “solar cells” change sunlight directly into electricity. PV cells are grouped into panels and panels are grouped into arrays. PV cells can be used in a wide range of applications from a few cells powering a calculator, to a bunch of panels that power single homes, to many acres of panels that become a large solar power plant.

The benefits of solar energy are:

  • Does not produce air pollutants or carbon dioxide
  • Sunlight is abundant
  • Generate electricity directly from sunlight and have no moving parts
  • Greatest energy source when air conditioning demand is highest
  • Minimal maintenance
  • Minimal impact on the environment

Energy from Wind

Wind, which is caused by the uneven heating of the Earths surface by the sun, can be used to generate electricity. A wind turbine is used to collect the wind’s kinetic energy from its blades and converts the motion of the blades to electricity with an electric generator.

The benefits of wind energy are:

  • Sustainable
  • Costs continue to decrease
  •  Often more available during seasons with higher electric demand
  • Wind turbines do not release any emissions
  • Wind turbines have a small physical footprint

Energy from Biomass

Biomass is organic material from plants or animals. When considering the process of photosynthesis, biomass essentially contains stored energy from the sun. When burned, the chemical energy from the biomass is converted to heat and can be converted to electricity. Biomass is renewable because new crops can be grown in a relatively short period of time and they will always create waste. Examples of biomass fuels are wood, crops, manure, and garbage.

The benefits of biomass energy are:

  • Widely available and abundant
  • Generally low-cost inputs
  • Can be domestically produced for energy independence
  • Low Carbon (carbon neutral) and generally cleaner than fossil fuels
  • Minimize negative environmental impacts of landfills and farms

Energy from the Earth

Geothermal energy is generated from the heat from within the earth. The heat can be moved to heat buildings or generate electricity. Heat from the earth is constantly replenished and thus renewable. The three main uses of geothermal energy are: direct use for heating systems, electricity generation power plants and geothermal heat pumps.

The benefits of geothermal energy are:

  • Emission free with no carbon emissions
  • Can scrub out sulfur which would have been otherwise released
  • Requires no fuel, mining or transportation
  • Not subject to the same fluctuations as solar and wind
  • A small land footprint
  • Simple and reliable
  • Can provide base load or peak power
  • Cost competitive

Energy from Water

Hydropower is energy produced from moving water. Since hydropower relies on the earth’s water cycle to replenish the water supply, hydropower is considered renewable.



Two main sources of hydropower are the natural run of rivers and storage systems such as a dam. Mechanical energy is harnessed from the moving water from these sources and can turn an electric generation turbine to produce electricity.

The benefits of hydropower are:

  • Electricity generation itself does not pollute environment
  • Flexibility - adjusting the water flow and electric output is easy
  • Compared to fossil fuels and nuclear energy, hydropower is much safer
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