Options for a Better Energy Future

Efficiency & Conservation Solar Wind Bioenergy Geothermal Hydropower Ocean Hydrogen

Renewable Energy

The world relies largely on fossil fuels to meet demands for energy, and energy supply, delivery, and use practices are typically quite inefficient. Yet these resources exist in finite quantities, and oil and natural gas are becoming ever more costly as worldwide demand grows and existing supplies are depleted. Fossil fuel extraction and combustion also harm the environment and are changing the Earth's climate, with potentially disastrous economic, environmental, and social impacts.
    Energy conservation and efficiency - including clean vehicles and green buildings - make each unit of energy go farther. Renewable sources of energy are continuously regenerated by natural forces that can be harnessed with limited or no adverse impacts and whose costs are largely immune to the laws of supply and demand.
    Renewables are dependent, in large part, on the sun. Solar energy may be used directly for heating and for the generation of electricity. The sun's heat is also the key driver of wind, whose energy may be tapped and converted into green power via wind turbines. Sunlight is essential to plant growth as biomass, which can be used to generate electricity and heat and to drive vehicles in the form of bioenergy. The water cycle, driven by solar-heated evaporation at the Earth's surface, condensation in the atmosphere, and precipitation, yields another renewalbe resource: The kinetic energy of water flowing downhill—typically rivers and streams—may be tapped as hydropower.

Photovoltaic panels being installed in Woods Hole, Massachusetts

    The ocean is a vast reservoir of energy that may be used to generate electricity. It is possible to harness the energy of ocean tides, dependent upon the gravitational influence of the moon and sun, and ocean waves, which are controlled largely be wind. The ocean’s thermal energy, produced by the solar heating of surface waters, may also be utilized.
     The Sun and the Earth’s internal heat create geothermal energy. This energy may be harnessed by utilizing the near-constant temperature of shallow groundwater (between 50° and 60°F, or 10° to 16°C) for heating and cooling purposes. In addition, geothermal reservoirs of hot water and hot rock may be tapped for their heating potential and for electrical generation.
    Widespread adoption of renewable energy has traditionally been limited by unfavorable economics, irregular distribution, intermittency, and other factors. There is great hope that these barriers will be offset in the future by policy changes and technological advances and, perhaps eventually, by widespread availability of hydrogen acting as a storage medium for energy garnered from renewable sources.
    Recent advances, combined with expanded application experience, are making renewables increasingly cost-competitive with conventional fossil-fuel-based systems. The rate of technological progress is accelerating, public awareness of the adverse impacts of fossil fuels is growing, and policy frameworks that level the playing field for renewables are emerging. These trends augur well for a green energy future in the Cape & Islands region and beyond.

Visit the Cape & Islands Energy Information Clearinghouse and the Cape & Islands Go Green Guide (CIGoGreen) for more information.