solar energy

Introduction to Solar Energy

“Because we are running out of gas and oil, we must prepare quickly for a third change, to strict conservation and to the use of…permanent renewable sources, like solar power”. These are the words of former US president Jimmy Carter. Solar energy has stood the test of time with its use dating as far as the history of humans.

Every hour, the sun strikes the earth with over 430 quintillion joules of energy. The power is enough to sustain all the activities that require electricity for a whole year. But what have we done to tap the enormous energy from the sun?

The sun is a source of an electric and thermal form of usable energy known as solar power. There are different ways to tap it. One of them is the use of photovoltaic solar panels. It is the most common method of capturing this energy. It converts rays from the sun to electricity. Additionally, solar power is crucial in indoor regulation of temperature.

You can install hot water heating systems on your residential and commercial properties. When designing your house, you should consider how you can utilize solar energy.

Scales of Solar Energy Installation

There is utility, residential, and commercial scale. The residential scale involves mounting of 5-20 kilowatts solar panels on the rooftop of your homes. The size of the roof is the determining factor. Additionally, installing the panels on open land is possible, which is known as ground-mounting. When it comes to commercial solar power projects, the installation scale is larger compared to residential solar.

Individual solar mounts can differ in size, but commercial-scale solar projects work for a consistent reason. That is to offer on-site power to business premises and non-profits. The third scale is the utility solar power project. Such a project is typically large, with numerous megawatts and supply energy to many utility clients.

Community solar projects come in handy for those who can’t mount solar on their property for several reasons. It is a feasible option that establishes a connection between residential clients and utility-scale solar projects.

This program involves building a solar farm on certain middle sites for use by the community around, rather than installing on an individual’s property. Therefore, residential consumers won’t have to mount the panels on their building. But they stand to benefit from the community’s solar project through enrollment and subscription.

An overview of how solar works

A solar panel consists of a metal frame, a glass covering unit, a layer of silicon cells, and wire connections for electricity flow from the cells. Silicon is a non-metal but is a good conductor. It allows absorption and conversion of sun rays into usable energy.

Once sunlight strikes a silicon cell, it triggers motion in the cells, which initiates electric current flow. The activation describes the overall mode of work of a solar panel known as the photovoltaic effect. It is a discovery of Edmond Becquerel in 1839. The scientific theory of producing electricity using solar energy lies in this effect. There are materials referred to as semiconductors to allow them to generate electric current when hit by sun rays.

The whole process involves:

  • Absorption of solar radiation by the silicon cell
  • The radiation interacts with this photovoltaic solar cell and triggers the movement of electrons. This results in a flow of electric current.
  • Cables conduct the direct current (DC) electricity to a solar inverter. It is in the converter that DC converts into alternating current (AC). It is a prevalent form of electricity in the United States.

On average, 5% of the solar modules available in the global market are thin-film photovoltaic. They have at least one semiconductor on a single substrate’s surface instead of creating a panel from numerous cells. For long, thin-film photovoltaic has been less efficient than crystalline silicon in the conversion of solar radiation into electric energy. But they are cheaper to construct, and the technology is becoming more popular in the United States.

Besides, the utilization of multi-junction cells is more efficient compared to traditional solar cells. They harness more solar energy. Instead of complete reliance on one semiconductor e.g., silicon, these cells have multiple layers. Each of the layers has a semiconductor component that reacts to a different range of the light spectrum. Although it is expensive to use technology, it is likely to be more viable commercially in the next few years.

History of solar energy in the United States

In the larger 20th century, commitments to utilize solar power focused on the sun’s heat properties rather than electricity. The first commercial introduction of water heating systems was in California, nine years into the 20th century. It is only 64 years that they became more popular in the United States after installing a solar array in the White House by President Jimmy Carter. The hot water from the system was crucial in the laundry and cafeteria.

Bell Labs came up with the first silicon photovoltaic cell in 1954. Even though previously, there were several methods used to absorb and convert solar radiation into usable energy. However, only after the developments of Bell Labs could it become possible to tap solar power and use it in powering electric devices for long.

At first, solar panels were four percent efficient ion converting solar radiation to electricity. But today, you can find a solar module with an efficiency of 20 percent in the United States. Additionally, it is even likely to go above that in the next coming years.

People were slow to adopt solar power at first. But the move by several state and federal authorities to come up with incentives and policies caused a reduction in the cost of solar modules that saw a wide spread adoption.

Current trend in solar power in the United States

There is a lot of hope in using solar energy as a non-carbon releasing source of power. However, only around 2.3 percent of the electricity in less than one percent of the total power supply in the United States is from the sun. Significant policy changes are essential at all levels of the government. Such is possible through fast-tracking the shift to an economy that relies on energy from the sun and other renewable energy sources.

The National Renewable Energy Laboratory notes that solar mounts on the rooftops in the United States could produce enough electricity to offset more than 35% of the current electrical energy requirements. However, the realization of such potential may take time. In 2018, a combination of solar systems, including rooftops and solar parking canopies, generated around 30 billion kilowatt-hours of electrical power. That is slightly above 0.7% of the total power production in the United States.

Solar energy is a marginal contributor to the total electricity supply in the United States. However, it is coming with a significant transformation in how people generate and use electricity. Utility companies have dominated the provision of electric power to consumers in the United States. The firms, together with cooperatives, depend on nuclear power, fossil fuels, and hydro-power. But today, net-metering regulations in most states call for utilities to provide compensation for the extra electric energy they produce in their residential and commercial areas. However, it has led to disputes with utilities citing inadequate compensation for the supply lines and backup power that they still supply to all clients.

The cost of solar power in the United States

This energy cost has significantly gone down, concurring in the increase in solar modules’ efficiency. The cost of mounting went down with around 60 percent in the last decade. Many professionals in the industry forecast that the fall will be even more in the next few years.

Besides, incentives and rebates on solar energy will significantly lower solar energy costs, depending on the state. At the national level, the Federal Investment Tax Credit (ITC) is among the significant incentives for anyone interested in solar energy. It allows a 26 percent deduction on the cost of a solar installation project from federal tax. However, this incentive is short term and will lower to 22 percent in 2021. After that, it will be at zero percent in 2022 for residential solar projects.

Several states across the country have more incentives that, when combined with the federal Investment Tax Credit, lowers solar energy cost more.

Solar power is a renewable source of energy

Solar power is clean and cheap. Besides, it is a renewable energy source that people can exploit anywhere in the continent, provided there is sunlight hitting the ground surface. The fact that it comes from the sun means that the source of power has no limit. Renewable energy tech produces electric power from infinite resources. Take, for instance, generating energy from fossil fuels.

The oil, gas, and cola take many years to form. Therefore, whenever you burn the resources to produce electricity, you are always in the process of depleting them. Using renewable sources such as solar, water, and wind to create electric power does not lead to depletion. Sunlight consistently hits the earth surface, and after converting it into electricity, the source remains for future use.

In the US, the total electricity supply includes a mixture of renewable sources such as solar and fossil fuels. The non-renewable sources that are fossil fuels make up the larger component. However, solar energy is quickly picking up. It appears to be concurrent with the cost of solar.

Like other sources of energy, solar has its environmental impacts. Take, for instance, the Utility-Scale projects. They can d e a challenge taking into consideration the size of the land they consume. Therefore, one common approach to cushion areas with vegetation is to use unproductive lands. They could be waste sites and abandoned mines. Some developers are considering reservoirs to mount floating solar modules.

Stabilizing the supply and demand for solar power

Solar energy varies such that there are times when there is more electricity generation than needed. On the contrary, there is no production of electrons when there is no sunshine. Therefore, there is a need for strategies to keep up with the pace of power requirements.

One potential tool is the demand response. Clients can command their electric utility to cut off or reduce the running of certain appliances such as water heaters and air conditioners when the energy demand would outdo clean power distribution. The appliances are programmable to operate when there is enough electricity freely.

Besides, it is also possible to stabilize a power distribution that majorly depends on renewable energy by extending the grid’s geographical reach. However, that alone won’t lead to a stable grid. Energy storage would do better.

The fast growth in the country’s adoption of solar energy has resulted in developments in adjacent areas. Note that electric vehicles and systems for power storage are two segments that will increase parallel to solar energy by augmentation of solar advantages.

Solar modules will only generate electricity when there is sunlight. Therefore, it is increasingly becoming essential to store the solar panel’s energy throughout the day. For instance, solar batteries are crucial in storing electricity that is then usable when there is little production. Solar power storage solutions are essential in all the three scales of solar panel mountings. They come with several added advantages, including lower costs of power and reliable energy. Additionally, storage solutions are critical for grid resiliency.

The wave of solar power adoption will get a boost and positive impact from electric vehicles. The reduced cost of maintenance and fuels is an essential invention in the next few years. Besides, electric cars have a less environmental footprint, unlike conventional vehicles that use internal combustion mechanisms. The increase in the embracement of these vehicles comes with increasing demand for electrical energy to run them.

Solar energy is a perfect fit for them. As the country and the world gears towards complete electrification of residential houses, solar energy is one of the most reliable and cleanest ways of supporting an electrically powered future.  Besides, it is less expensive.

Utilities are changing their game

Utilities do not show much interest in supplied solar, but mossy are coming up with their solar installation projects. The move complies with the renewable electrical power standards that require a minimum proportion of the retail sale of electricity in most states to be from renewable sources. Berkeley Lab cites that the standards led to a boost in about 50% of all renewable electricity potential and power production for 17 years from 2002.

Additionally, federal policies have come with a positive impact on solar energy. An ITC of 30 percent that had been in force from 2006 has been crucial in fetching investment funds to solar utility projects. Besides, it has led to the affordability of solar energy to residential and commercial enterprises, especially those whose tax liability is adequate. But the fact that tax credit won’t be available soon may reduce the general investment in solar. However, utilities will continue constructing big photovoltaic projects.

Lazard notes that the cost that the flattened cost of a large scale photovoltaic project ma range between 36 to 46 dollars per megawatt. Therefore, it is less expensive compared to new nuclear power, which costs between 101 and 191 dollars per megawatt.

Challenges facing the solar sector

The import tariff on solar modules is one of the threats facing the United States’ solar sector. They have led to a loss of more than 62,000 employment opportunities and around 20 billion dollars in private developments. Besides, the tariffs lead to an unbalanced impact on projects in areas with less sunlight.

Growth Trajectory of the US solar industry

Currently, the solar energy industry in the United States provides employment opportunities to about 240,000 people. Additionally, it adds billions to the economic value of the country. The United States had more than two million solar photovoltaic systems by October 2019. That adds up to 71,300 MW of solar potential and producing more than 100 TWh.

In the previous year, solar contributed to around 1.5 percent of the United States’ electrical power. Furthermore, forecasts are that the sector will be the fastest in growth for around the next three decades.

In the next five years alone, the total capacity of mounted photovoltaic capacity will likely see an increase of more than 200%. It is evident through interlinks between Texas, Mid Atlantic, and California. Regardless of that growth, solar PV installation will be the quickest growing occupation for some years.

Leading states in the United States

The solar PV capacity in California is more than 26,000 megawatts. Therefore, it is the leading state in the country on matters of solar. The second state is North Carolina, which happens to have about five times less than California. In the next few years, the states that are likely to lead in solar PV capacity other than the above mentioned include Nevada, Florida, and Texas. Projections are that they will have around 505 of the total capacity in the country.

Global comparison of the US solar sector

The number keeps fluctuating. However, the country was second in deploying solar PV after China by the end of 2018. By 2050, the predicted growth estimates are 300 GW/year or more, with northern states expected to contribute 20% of the total.

Solar power does not release toxic emissions into the atmosphere that can harm the environment and living things. Besides, it does not contaminate the water. Solar energy competes effectively in several parts of the United States. Global warming in the United States could decrease significantly in the next few years if electricity generation focuses on solar power. Therefore, this renewable source of energy offers a sustainable solution that is not only economic but also environmentally sound.