Perhaps you want to live off the grid, decrease your carbon footprint or limit your dependency on those utility companies that ask for so much money every month. While we’ve previously covered some of the ways you can decrease your energy use, it’s also possible to use renewable energy sources to virtually eliminate your utility bills.

If you’re installing renewable energy sources, it’s important to obey your local building codes, as set by your municipality. You may be required to keep your home connected to “the power grid,” but it’s possible that you’ll be able to rely on your chosen source of renewable energy instead.

All renewable energy sources will come with an upfront cost. If cost is an important factor for you, then it’s important that you investigate those costs for your area, and do some math to see if and when switching to renewable energy will pay off. On the other hand, if you feel that cost is less important than the incredibly positive impact this change will have on the environment, read on to learn more about five of the most worthwhile types of renewable energy available.

Solar Power

It was Albert Einstein who was first able to describe the process of harnessing energy from light. Later, Bell Laboratories created the first solar-powered battery, but this technology was still far too expensive to be made accessible to the general public. However, as space programs began to utilize solar energy and manufacture solar panels, it became more cost-effective and its use became more widespread.

Energy from the sun is harnessed by solar panels, which are made of photovoltaic cells. Photovoltaic cells have a few basic components: a front contact, a back contact, an anti-reflective coating (to prevent any light from being reflected away) and a semi-conductive material with a positive side and a negative side.

These cells create a low flow of direct current (DC) energy by capturing light, which releases electrons from atoms in the semi-conductive material and allows them to flow freely within a circuit, creating a current of electricity.

To be able to use the electricity generated by a solar panel, a power inverter is required to invert it from DC to AC (from a direct to an alternating current). Some systems use a single “string” inverter for all the solar panels, while others may use a microinverter for each individual solar panel.

The main advantage of being connected to the power grid with a solar power system is that if solar energy falls short, then the power grid can fill in the gaps. Additionally, if you have extra solar energy, it can be returned to the power grid, and you can often get rebates from your utility company for this.

Geothermal Power

A geothermal system uses the consistent temperature inside the Earth to regulate the temperature in your home. Geothermal science can also create electricity by using the steam from hot water underground to spin turbines (more on turbines below!).

Geothermal pipes need to be buried at least four feet underground, so virtually any home can use geothermal heating and cooling. One limitation that comes with geothermal electricity is the necessity of an underground heat source, such as a hot spring, that can generate steam.

Wind Power

Wind power is harnessed through the use of turbines. Each turbine is connected to a rotor that spins and does some sort of work. In ancient history, this work often involved milling corn or wheat with a waterwheel or windmill. Now, we can attach a generator to that rotor and create electricity!

A rotational speed of between 1000 and 1800 revolutions per minute is required for the generation of electricity, which is why a simple wind spinner can’t be used to charge your cell phone (unless it’s a very windy day!).

In the case of wind power, propeller blades form the turbine that catches wind in order to spin, which then spins the rotor and a low-speed shaft. The low-speed shaft only spins at around 30 to 60 revolutions per minute (rpm), which isn’t fast enough to generate electricity, so a gearbox is needed to harness that rotational power towards a high-speed shaft, which then powers the generator and creates electricity.

A single average wind-powered turbine can generate power for approximately 332 homes. However, the wind isn’t a reliable source of energy, so being connected to the power grid or other sources of energy is a helpful convenience for turbine users. Winds that are too low or even too high can prevent the effective operation of a wind turbine.


Dam collecting water for hydropower - 5 types of renewable energy all homeowners should investigate

Along the same lines as harnessing wind to operate a turbine, the power of water can also be harnessed to do work. Even a small stream of water can spin a turbine with enough speed to generate electricity.

Hydropower plants have channeled water power by creating dams or reservoirs that enable them to “drop” water onto a turbine and generate massive amounts of energy.

Tidal power and wave power are other forms of hydropower that can be utilized. Tides are even more predictable than wind or sun, which makes them a more reliable form of energy.

Tidal power has previously been costly, due to the change in flow velocity as tides come in and out. This makes it difficult, at times, to harness enough turbine speed (remember, approximately 1000 to 1800 rpm are required) to generate electricity. Fortunately, with the development of new and innovative turbine technology, this type of power is becoming less costly and easier to implement!

Biofuel and biomass

Mostly derived directly from plants or indirectly from agricultural waste, biofuels and biomass are produced through biological (rather than geological) processes.

While carbon dioxide is still emitted by the burning of these fuels, they’re considered to be carbon-neutral, due to the carbon dioxide that’s consumed by the plants during their lifetime. Also, since plants can be grown continuously (in stark contrast to our finite resource of fossil fuels), they’re considered a renewable resource.

The use of various forms of biofuels is still somewhat controversial, due to the social, economic and technical implications they create. Besides, many people seem to argue over whether or not they’re truly environmentally friendly.

As the world turns…

As the global population begins to shift its mindset toward one of preserving resources, the hope is that renewable energy sources will become more normalized and thus less expensive to produce and utilize.

While household energy use accounts for only a small portion of all the energy use in the world, we as consumers can have a tremendous effect on the direction the world takes in terms of ecological research, developing accessible and eco-friendly technologies (like “green” cars!), and more.

To read more on the topic of renewable energy, visit BioLEC: A way to power the world with plants and industrial waste»

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