Reflecting On Solar Towers

Solar panels are not an unusual sight as more of us search for carbon-free energy solutions. However, solar towers, while having been in development for forty-plus years, are more elusive even as they are being considered to replace traditional, fossil-fuel burning utility plants. If you have never seen a solar tower—currently there are only about a half dozen in the world, two of them in the United States—check out our video below for a sky-high view of one spotted by Force For Good founder, Jonathan Sprout, on the U.S. West Coast.

The basic design includes an array of mirrors, called heliostats, set around a large tower. The heliostats are computer controlled, moving continually throughout the day to best position themselves to reflect the sun’s rays toward a receiver atop the tower. The concentrated solar power (CSP) heats a liquid-salt solution which is used to create steam. The steam in turn drives turbines that make electricity. A useful way to blow off a little steam, right?

The environmental advantages of CSP systems, according to an article in Mother Nature Network, are impressive: “Compared to fossil-fuel burning plants like coal or natural gas, there's no air pollution, water pollution or greenhouse gases typically created in the energy generation process.” But these systems have disadvantages, too. “There are some emissions created in building a solar tower, just as there would be in another type of power plant, since materials have to be moved to the location and built, all of which requires energy, usually in the form of fossil fuels… Some toxic materials are used to make the components of the plant (in this case, photovoltaic cells).”

The local ecosystem is effected if the system uses water for cooling or cleaning. Biodiversity is impacted not only when land is cleared to build the power towers but the concentrated heat kills birds and insects in its path so mitigation measures must be followed. Finding ideal areas are a challenge as flat and dry locations with minimal wind is most efficient. And of course, you need a lot of sun. “Solar towers are often constructed in desert landscapes, which by their very nature are somewhat fragile, so special care must be taken in siting and construction,” states the Better World Solutions website. But as the world moves towards renewable energy, we may see more solar towers in our travels.

You can read more Here and Here

— Leslie Chew & Hillary Black, Force For Good

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Earth Day 2020

April is Earth Month, a time set aside to focus on the importance of a healthy planet and the actions we must take to make it so. To participate as a community, we come together on April 22nd each year to celebrate Earth Day. Earth Day creates awareness about environmental issues and actionable steps to bring about positive change. This year, 2020, we celebrate Earth Day’s 50th birthday!

The first Earth Day in 1970 was a response to the realization that we had created an environmental crisis. Smog was thick at unhealthy levels, oil spills were occurring much too often and with minimal corrective action, and rivers had become so polluted they were on fire. According to EarthDay.org, on April 22, 1970 an unprecedented 10% of America’s citizens at the time—20 million—took to the streets in protest. 

Some say that Earth Day launched the modern environmental movement. In response to citizens’ cry for action, the Environmental Protection Agency (EPA) was founded on December 2, 1970; the Clean Air Act of 1970 was established; and the Clean Water Act was passed in 1972. Throughout the decade, the EPA went on to define Air Pollution Danger Levels, set National Air Quality Standards, and create the Automobile Pollution Control and Auto Maintenance Regulations among many other beneficial oversights. Today, 50 years later, human population growth and industrial impacts on Earth’s resources persist while scientific evidence supports the critical need for global environmental protections policy, personal actions for stewardship, and maintaining or increasing protections already achieved. Fittingly, 2020’s Earth Day theme is Climate Action.

This year, due to the COVID-19 outbreak, Earth Day gatherings have gone digital.

So, while you’re staying safe by staying home, you can still participate in Earth Day’s 50th anniversary. Visit the Earth Day sites below and others for virtual ways to engage and take action. You can stay safe, help heal our priceless Earth and be a Force For Good. For more visit:

https://www.earthday.org/coronavirus-drives-digital-striking-movement/

https://www.earthday.org/earth-day-2020/

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Using solar energy to power your home can be a great way to both help fight climate change and save money by lowering your electric bill.

An energy source for decades, solar panels can be found on residential and commercial rooftops, city and county roadside signs, in stadiums and on spacecrafts. Solar panels work by taking the sun’s energy and changing it into electricity. Comprised of many individual cells typically made from silicon (a semiconductor most commonly known for its use in computers), the silicon cells, when exposed to sunlight, generate electricity in a process known as the “photovoltaic effect.”

We’ve been experimenting with the photovoltaic process for almost two centuries. The photovoltaic effect—first documented by French physicist Edmond Becquerel in 1839—is the generation of voltage and electric current in a material upon exposure to solar radiation. In most photovoltaic usages the radiation is sunlight and the devices are called solar cells. The sun is basically a nuclear reactor. It releases small bits of energy called photons. These photons then travel 93 million miles from the sun to Earth in under 9 minutes. The sun emits enough photons in one hour to generate enough power to meet current global energy requirements for an entire year. I’d say that’s a great resource.

To harness that resource for our home, a collection of solar panels are installed on the roof. The solar cells absorb the energy from the sunlight and electrons begin to flow and generate an electric current. Electrical wires capture the current from each panel and combine it with the current from the other panels. This initial current is DC, direct current. Since all of the appliances, lights and equipment in our home use AC alternating current to operate, a device called a solar inverter is used to convert the DC current to AC current. The wires then take the collected DC current to the inverter and additional wires take the AC current out of the inverter and into our electrical panel to power our home. If our home produces more power than we need, the surplus energy gets sent back to the power grid and we get credit on our bill. This process of giving power back is called Net Metering.

If you’re interested in adding solar power to your home for cleaner energy and financial benefit, it is recommended that you do some research and consider all of your options. Contacting your power company, getting quotes from multiple installers, and talking with you neighbors, especially those who have installed solar panels, are a few of the things you can do. Good luck and keep your sunny side up!

—Leslie Chew, Force For Good Technical Advisor

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