Home >Article >What is Alternative Energy?

What is Alternative Energy?

Apr 3, 2012

Mention alternative energy and what’s the first thing that comes to mind? Usually those futuristic-looking sleek, white turbines turning in the wind or banks of solar panels powering a house or building, right? But here’s the thing: alternative energy is so much more than that and better still, thanks to improvements in technology, it’s now more accessible to American homeowners than ever before.

What is alternative energy?

Alternative energy, also called renewable energy, is energy that’s produced from natural resources such as sunlight (solar energy), wind, water and geothermal heat.

Solar Energy

Currently, there are multiple ways the sun’s heat is converted to energy, including:

  • Thermal panels, which trap the sun’s rays and convert them to heat air or water
  • Photovoltaic Panels, which convert the sun’s rays into electricity
  • Passive solar home design, in which houses are specifically designed or retrofitted to collect and store the sun’s energy

Pros to using solar energy:

  • Renewable
  • Pollution-free
  • Efficient
  • Avoid high cost of utility power lines being extended to remote communities

Challenges to using solar energy:

  • Cloudy skies and night time limit energy production
  • Your home may not have the optimum orientation

Wind Power

Wind energy is collected by using wind power to rotate the blades of wind turbines, which convert the kinetic energy in wind into clean electricity through the use of a generator. Countries all over the world have invested in ‘wind farms’ that consist of large banks of turbines to provide electricity to residential communities. In the United States, homeowners can invest in Small Wind Electric Systems that can help lower electricity bills by as much as 50%-90%, as well as continuing to provide electricity during power outages.

Pros to using wind power:

  • Renewable
  • Pollution-free
  • Wind turbines can be built on land used for farming and grazing,
  • Avoid high cost of utility power lines being extended to remote communities

Challenges to using wind power:

  • Wind potential is very site specific
  • When wind is less, power generation decreases

Hydroelectric Energy

Hydroelectric power is generated in 2 ways:

  1. Energy from dammed water that’s used to drive a water turbine or generator
  2. Energy from undammed sources, such as ocean tidal and wave power

Whereas ocean energy generation is more geared towards powering large communities or industry, homeowners and small business owners can take advantage of Microhydropower Systems to generate their own energy. While microhydropower systems generate upwards of 100 kW of power, a 10kW system can create enough electricity for a large home, small resort or a hobby farm by using the energy in flowing water to produce electrical or mechanical energy. Utilizing a process known as run-of-the-river, some of a river’s water is diverted to a channel or pipeline that delivers it to a turbine or waterwheel. Once there, the moving water rotates the wheel or turbine, which in turn spins a shaft, creating energy to be used for a generator (for electricity) or mechanical processes (pumping water).

Pros to using hydroelectric energy:

  • Pollution-free
  • Electricity can be continuously produced
  • Production can be increased or decreased upon demand due to damming system
  • Water used for the system can be re-used

Challenges to using hydroelectric energy:

  • Sufficient and powerful water supply is required

Geothermal Heat

Geothermal heat is heat that is generated from the Earth’s core and is a tremendous source of natural energy. Geothermal heat can be used to heat homes in 2 ways:

  1. Direct UseGeothermal reservoirs of low to moderate temperature heat can be used to provide heat to residential, commercial and industrial communities. There are many such reservoirs located throughout the Western United States, providing a tremendous potential for direct use applications. Direct use systemsnormally consist of 3 components:
    1. A source, like a well, which brings the hot water to the surface
    2. A mechanical system, such as piping, that delivers the heat to the target space
    3. A disposal system, an injection well or storage pond, for example, that will receive the cooled geothermal fluid
  2. Geothermal Heat PumpsRegardless of the temperature above, a few feet below the ground’s surface, it remains relatively constant, ranging from 45°F to 75°F, depending upon where you are. A Geothermal Heat Pump (GHP) uses this as the heat exchange medium instead of the outside air temperature. As a result, a GHP is extremely efficient, reaching up to 300%-600% efficiency levels on the coldest winter nights, as opposed to 175%-250% for air sourced heat pumps on cool days. GHPs are quieter, last longer and only require minor maintenance as compared to their air source counterparts.

Pros to using geothermal energy:

  • More efficient
  • Less expensive than traditional fuels
  • Produces far fewer (in many cases none) air pollutants than fossil fuels

Cons to using geothermal energy:

  • Initial investment cost can be high, but this is recouped over the life of the system, which is longer than air source systems

If you’re interested in alternative energy solutions for your home, contact your local RESNET Certified Contractor to learn about what options are available to you.