What Makes Energy Renewable?
Wind, solar, hydro, geothermal, and biofuel are all energy sources that are increasingly in the public view. The backbone of energy across the world has been coal for a long time. In the past few years, there have been countries making great strides in moving away from the standard of coal power generation and shifting over to renewables. Just last month, Portugal ran their entire country on renewables only for four consecutive days. In the past year we’ve even had solar and wind production moving into a majority for electricity production in multiple countries.
Geothermal Energy
Geothermal system with cutting through the earth and deep hole
Coal, wood, oil, and even atomic energy have all operated on the same principle: steam. Water is heated into steam and pressurized. Pressurized steam then spins a turbine to generate electrical energy (or mechanical energy in the case of steam locomotives). In most cases, renewables are more efficient because they lack a steam cycle. Geothermal takes advantage of the steam cycle without the high fuel-costs by simply using heat generated from the Earth itself to generate steam for a turbine.
Overall thermal efficiency from geothermal energy is lower than other steam-powered turbines, since it cannot quite reach the same temperatures as fuel-fired turbines. But, geothermal only needs a pumping system to be able to move the heated fluid from within the earth. Geothermal heating can be used either directly or passively, generating electricity or simply heating water and homes. Geothermal energy stands out amongst renewables because it doesn’t have a variable energy source. Heat from inside the earth is always readily available once it’s reached.
Solar Energy
Solar Farm
From science fiction to massive solar plants in the American West, solar energy has fascinated and tantalized scientists and writers for generations. The promise of easily-accessible, virtually free energy from the large fusion reactor at the center of our solar system (the sun) is enticing and we’re getting closer to harnessing its power effectively every day.
Solar power is interesting because it’s one of the few electrical energy systems that does not use a turbine to generate energy. Photoelectric cells contain a material that releases electrons when hit by a photon, generating electrical power. There are no moving parts, no fuel to burn and pay for, and only occasional maintenance to keep the system performing optimally.
So what is holding back the proliferation of solar energy? Space and storage. We can generate large quantities of energy from solar, but we do not, at present, have the right method to store that energy for periods without sunlight (night time and storms). So far the best response has been homeowners installing solar cells on their own homes with battery storage systems linked into their own neighborhoods. By splitting up generation and storage within the neighborhood itself, enough solar cells can be installed to generate energy both day and night.
Space is at a premium when it comes to energy generation. Solar power plants take up more space than traditional plants, while generating less energy per square foot. Because solar cells need to be placed over large areas to maximize sunlight, installing power plants in urban areas can be difficult. Though installing solar cells on your home can be done simply.
Wind Energy
Wind Turbines Farm
Quiet, bearing a tiny footprint, and requiring no fuel for operation, wind energy has become a front-runner for renewable energy generation all over the world. From offshore turbines to the appearance of more wind turbines than oil wells in the Midwest, wind is here to stay and its doing well.
Wind energy takes up a lot of space, but each individual turbine takes up a very small plot of land, making it simple to spread the production across a vast area without directly affecting most of the environment.
Wind energy is clean, and is becoming so efficient that these turbines can be installed in most part of the world for backbone and supplemental energy generation. Why haven’t we switched over to wind energy exclusively? For one thing, relying on a single source of energy, especially one with a variable energy source, is dangerous in the event of power losses. Wind turbines are also not capable of self-starting. The computer and energy management systems for these turbines require power to already be applied, meaning that, until we have better energy storage or can supplement their power off-site, wind energy cannot be our fail-safe due to occasional blackouts.
Hydroelectric Power
Hoover Dam, Hydroelectric power station on the border of Arizona and Nevada.
We mentioned self-starting or “œblack-start” energy systems. These systems can be started without power applied to the system, a huge benefit to fuel-fed power plants, and necessary in the event of major blackouts and power losses. True, we can supplement with gas turbines or nearby power generation, but we also want black-start renewables. Fortunately, hydroelectric power plants require no off-system power to function.
Hydroelectric plants are special because, while they also have a somewhat variable energy source, they also have one of the best energy storage systems available: potential energy. Hydroelectric dams use flowing water to spin turbines, typically generated from lakes and rivers. Rather than storing generated electricity, hydroelectric plants can store water at a higher altitude. By storing water in special tanks, they have access to electrical generation potential by simply releasing the stored water and allowing it to spin the turbine. Hydroelectric power is perfect for energy storage, but they’re limited to specific areas.
Biofuel & Biomass
Biofuel or Corn Syrup Gasoline
While they aren’t as prevalent as sunshine or wind, plants grow very quickly. Even slow growing plants grow faster than fossil fuels can be formed. Biofuel and biomass power plants function through combustion, allowing them to be used as effective replacements for gas-turbine power generation. By converting plant material directly into fuel we can circumvent the need for replacement fossil fuels which cannot be produced anywhere nearly as quickly as grown crops.
Like any other generation system, biofuels have their own drawbacks, such as use of food-land for fuel, large water requirements, and emissions from burning bio-fuel. But if we’re looking for a more easily replaceable fuel-source, biofuel is an alternative.
Hickerson Electrical is your source for all home electrical services.  We’re ready and willing to deliver top-quality service to your home at a moment’s notice. So call today at (703) 594-3913.
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