As the threat of climate change increases, we’ve seen more and more renewable options come to the forefront.
Solar energy is a renewable, carbon-free resource that is available all over the USA.
How does solar work?
The amount of energy from the sun that comes into contact with Earth’s surface is so many thousands of times greater than the Earth’s demand for power it is remarkable. Solar energy is produced either through photovoltaic cells or by the use of mirrors concentrating the heat of the sun and converting that into energy. This energy can be used to generate electricity or be stored in batteries or thermal storage.
Most people think of photovoltaic (PV) cells and panels. Photovoltaics work by absorbing photons from the sun into a unique chemical matrix which allows the migration of electrons to the valence band – meaning they have adequate energy to travel through a conductor. This is essentially how photovoltaic panels collect the energy from the sun and convert it into electricity.
Another form of solar energy is known as concentrated solar-thermal power. CSP uses mirrors to reflect and concentrate the photons, or energy, from sunlight and utilize it as thermal, or heat energy, which in turn is utilized to produce electricity.
What does the future of solar look like?
In the United States, less than 2% of total electricity is produced from solar. The renewable nature of solar electricity and the potential energy the technology could offer mankind make this means of producing electricity especially attractive for a carbon-conscious future.
The future of solar has much to do with technological improvements as well as logical and even clever implementations intended to get the most out of the technology. Finding efficient and cost-effective locations to install solar is one key to a more prolific future.
One means of producing electricity from solar which offers efficiency and suitable land is called agrivoltaics, exploits existing agricultural land to instal solar panels. The solar panels are installed such as to be elevated above the crops or even grazing livestock. The agricultural land offers several advantages – one, agricultural land eliminates the need to find land that is undeveloped. It also offers lands that have adequate solar energy potential.
Lastly, and most interestingly, current photovoltaic technology loses efficiency at high temperatures. Crops help mitigate this issue; water retained by crops evaporates in hot temperatures and acts sort of like sweat does, cooling the area around the plants, thereby improving the efficiency of the solar panels.
Working off of the same concept as agrivoltacis, floatovoltaics utilizes bodies of water, possibly a reservoir or even a naturally existing body of water. The solar panels are placed upon this body of water – utilizing available space and cooling the panels with the water upon which they are installed.
PV Trackers and Other Means To Get All The Light Possible
PV trackers, or photovoltaic trackers, are a technology which is intended to improve the efficiency of existing and future solar farms by moving the panels throughout the day in order to absorb the most possible sunlight. Photovoltaic cells are most efficient when they are faced directly at the sun, rather than at an angle. The closer to head-on the angle of the sun’s rays, the better. A PV tracker changes the angle the panels are positioned at throughout the day and year to maximize the energy a panel can absorb at a specific location.
Though this does consume between 5-10% of the energy a panel will produce on average, they result in more efficiency, gaining as much as 45% more output thanks to the PV trackers. This technology is most beneficial the further from the equator they are.
Other, similar technologies use mirrors to direct the sunlight. The mirrors, which can be considerably lighter in some implementations, can be more efficient. They can also be curved, potentially allowing improved efficiency without the need for moving parts. This technology can be used in photovoltaics as well as concentrated solar-thermal power.
Transparent Solar Cells and “Solar Windows”
New materials have been discovered which allow for the production of infrared-absorbant photovoltaic materials that could appear transparent to visible light. Such solar cells could be utilized in homes and other buildings to produce electricity virtually everywhere, most notably, from windows.
If all new windows could be photovoltaic, even small electrical production per window could go a long way in closing the gap between sustainable energy production and total energy demand. Though current examples of these transparent solar cells are not as efficient as silicon cells, they still produce around half the electricity compared to silicon, they are lighter and cheaper to produce, making for a promising technology.
Solar Thermal Fuels
Though not yet a “mature technology” according to MIT’s Tata Center, the potential for solar thermal fuels is immense. A solar thermal fuel is a compound or mixture that can absorb solar radiation and store it for a period, then release the thermal energy on demand as heat.
Though there is no singular technology, the concept follows a basic concept – photons are absorbed by a molecule, creating a reversible chemical reaction. This reaction is endothermic. When the reaction is reversed, however, the reaction is exothermic, reproducing the heat used to facilitate the initial chemical reaction. Typically, these reactions parallel those which occur in an eye, changing the conformation of an alkene from trans (more stable) to cis (higher potential energy) and then back again. This is one possible solution for the storage of solar energy.
How Can You Implement Solar Yourself?
Right now, solar has become affordable thanks to many state programs in conjunction with federal tax credits – and some financial mechanisms developed by solar companies themselves. The fact is, there has never been a better time to explore developing your own green energy system. Whether it involves geothermal, solar, wind, or a combination of these, a homeowner these days does have the power to control how they receive their power.
With new systems capable of storing electricity from solar effectively, and with simple installation and with systems easily adapted to the grid, there has never been a better time to consider generating your own power and leaving the fossil-fuel-burning power company in the dust. You even may profit by selling your energy back to the grid.
How does current policy promote expansion in solar?
Although current policies exist which encourage the use and development of solar power production and infrastructure, the reality is that much more could and should be done to promote the proliferation of this energy source as well as several others.
There are nearly 1,000 enacted bills in state legislatures since the year 2000 that mention solar energy. Many of these, however, deal with things like the inclusion of solar panels in the appraised value of a home or property, rather than establishing policy encouraging the adoption of renewables to help save our planet.
Such examples include state bills like Virginia’s 2018 omnibus energy bill, which designates growth in wind and solar to be in the public interest and establishes a myriad of implementations intended to make the development of these technologies – whether personal solar arrays or vast solar farms – more easily achieved and integrated into the grid. There are many such state bills like this, sadly, the states have limited power compared to the federal government to make meaningful change.
The key federal piece of legislation is the Solar Investmnet Tax Credit (SITC). This tax credit deducts 30% of any cost incurred in the purchase and installation of solar panels and subsequent systems designed to make the power useable in the home, office, or power grid. Since being enacted in 2006, the solar industry has grown by an inspiring 10,000%. Sadly, this tax credit is currently being drawn down, beginning in 2019, with residential credits ending in 2 years.
How could policy do better?
How could it not? There are plenty of incentives that could be created using legislation and policy – as evidenced by the overwhelming success of the solar investment tax credit – sadly, many of these programs were cut by the Trump administration and the Republican state legislatures across the country.
To start, extending the Investment Tax Credits indefinitely and including more renewable technologies outside of just solar and wind (currently covered), but also including geothermal at the very least. Beyond that, rejoining the Paris climate agreement would be another step in the right direction.
Finally, enacting legislation that comes with comprehensive infrastructure and power-plant development and construction guiding the way to a brighter future rather than simply offering tax incentives would be the ideal next step for solar and other renewables. Policy like the Green New Deal, though criticized, actually have a lot of merit – green technology still is an industry wide open with opportunity, and the United States still maintains a good amount of know-how and industrial capacity for manufacture in this sector. This could be leveraged to create a very profitable industry that allows U.S. made products to be sold and installed globally, creating jobs, investment opportunities, cleaner energy globally, and more economic security.
What are key advantages to expanding solar?
The key advantages to solar are first, it is a readily available and indefinitely renewable resource. It allows for the generation of electricity directly from sunlight, without the need to spin a turbine as many technologies do in order to produce electricity.
There are no emissions related to solar energy production, and technologies are being improved and developed all of the time which make the technology more efficient and practical. The cost of solar has consistently been going down over the past decade while the amount of energy produced from the sun’s rays has exploded since 2006.
What are key disadvantages to solar and expanding solar?
There are several disadvantages to solar power that should be considered.
First, the amount of space that must be used in order to produce enough energy to meet the nation’s and the world’s needs for electricity and energy.
Second, the cost associated with producing solar cells and panels, as well as the cost of their installation.
Third, the environmental impact associated with the manufacture of the solar cells and panels themselves.
Fourth, the life of the panels and the potential environmental cost of disposing of no longer viable solar panels. The fact of the matter is that most of the solar technology of today could potentially lead to some undesirable waste.
As it stands right now, solar panels are not easily recycled or repurposed, and their life expectancy sits at around thirty years on the longer end, meaning that in 20-30 years, we could have a serious problem in determining what to do with all of these solar panels.