• Renewable Energy Sources

  • We are committed to using renewable energy sources and working toward increasing their use all the time. Renewable energy can come from the sun, wind, biomass, earth and water.

    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 heat and electricity.

    When converted to thermal (or heat) energy, solar energy can be used to heat water, spaces or other fluids. 

    Solar energy can be converted to electricity in two ways:

    • 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.
    • Solar thermal/electric power plants generate electricity by concentrating solar energy to heat a fluid and produce steam that is used to turn a generator.

    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 

    The main limitations of solar energy are:

    • Sunlight is not constant - it varies depending on things such as location, time of day, time of year, and weather conditions
    • Relatively high initial cost for PV (Installation, PV panels, and Balance of System)
    • Requires expensive storage or grid connection to maintain uninterrupted electricity
    • Because sunlight is not focused on any one particular spot at any one time, a large area is required to collect enough useful energy.

     

    ENERGY FROM WIND

    Wind, which is caused by the uneven heating of the Earth’s 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

     

    The limitations of wind energy are:   

    • Wind resources are difficult to map and predict
    • The wind is not always constant
    • Some people do not like the visual impact of wind turbines on the landscape or the sounds the blades make while spinning around
    • Wind turbines are criticized for bird and bat deaths, although more deaths are caused by house cats and collisions with cars and buildings    

     

    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
    • Can minimize negative environmental impacts of landfills and farms


    The limitations of biomass energy are:

    • Energy intensive and expensive to produce and sometimes to transport.
    • Land utilization can be considerable and may lead to deforestation
    • Requires water to grow crops
    • Not 100% clean when burned
    • Can compete with food production
    • Some types are seasonal
    • Not easily scalable

     

    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

     

    The limitations of geothermal energy are:

    • Very location-specific - prime sites for generation plants are located near plate borders and not necessarily near large populations
    • Water usage
    • High construction costs when considering drilling
    • High level of planning and heat management

     

    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. Ocean tides and waves can also be a source of energy, however they are not as prevalent as the use of dams and rivers. 

    The benefits of geothermal energy 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

     

    The limitations of geothermal energy are:

    • Unpredictable environmental and biological consequences from the damming of water, changing water flow and infrastructure construction
    • Building power plants may be expensive
    • A drought could affect electricity generation and energy prices
    • Reservoirs that can be dammed are limited due to difficultly in siting