February 25, 2019 Solar Energy Written by Sara Popescu Slavikova
Solar Panels on Rooftop
The sun is the most powerful and abundant

source of renewable energy on our planet, and it’s no secret that recent technological innovations have made solar power affordable to more and more people [1].

In fact, 2017 was a year of a solar power boom, when a total solar capacity installed globally reached to 400 gigawatts (GW), generating about two percent of the world’s energy [2]. And that’s not where it ends.

Solar power has even become the fastest growing energy generation source. Many new small-scale and large-scale solar projects are planned in the upcoming years, to such extend that Global Market Outlook scenarios predict that global solar power capacity could triple by the end of 2022, reaching up to 1,200 GW [2].

Despite such a successful growth and technology development in the solar industry over the last years, solar power still features some technological constraints, mainly regarding photovoltaic cell efficiency, that limit maximum potential for energy generation from this abundant source.

If you have been considering getting solar panels for you home, it is good to know advantages and disadvantages of solar energy.

What are some advantages of solar energy?

1. Solar reduces your electricity bills

The main reason homeowners go solar is to save money. When generating your own electricity from the sun, you’re less dependent on utility companies, and that reduces your monthly electricity bill.

How much can you save with solar energy?

According to a report released by the North Carolina Clean Energy Technology Center, the majority of U.S. homeowners who invested in a 5 kilowatt (kW) solar photovoltaic system saved between $44 to $187 per month in their first year after the installation [4].

Quite impressive, isn’t it?

2. Net Metering – supplying energy to the grid

Besides directly saving money on your utility bills, solar module allows you to earn energy credits through the Net Metering Program. The program is aimed at grid-tied solar systems with the purpose of supporting homeowners like you to switching to renewable sources of energy.

Its principle is simple.

When your solar system generates more power than you consume, you receive credits from the energy company for supplying this extra energy to the grid.

Then, on days with low or no power generation from your solar system, your energy needs are drawn from the grid and the cost is covered by using these credits.

The good news is that you rarely have to pay extra fees, as the system often balances itself out throughout the year [5].

Solar panel installation work

You may also opt for a Value of Solar Tariff (VOST) which acts as an alternative to the net metering scheme.

The biggest advantage of VOST is that the program does not value your solar energy only by the electricity rate but also reflects benefits that solar adds to the grid.

VOST is fixed for at least 20 years in the US, while Net Metering fluctuates daily with the electricity rates.

3. Financial support from the government

The U.S. government offers a 30 percent tax credit for the installation of photovoltaic systems or solar water heaters. It is a dollar for dollar reduction in income taxes.

It can be taken on thirty percent of the amount of investment in the solar system (after any rebates) through 2019. Construction of the system must have begun by 2019 to take advantage of the full thirty percent credit.

This tax credit will drop to 26 percent in 2020, 22 percent in 2021 and then will no longer be available.

As of 2019, an average 5kW solar system costs around $15,250 before the tax credit. The 30 percent tax credit makes the cost of the solar installation come to just $10,675.

4. Return on investment

Based on the amount of money you save with your solar system, you can expect a return on your investment within the period of its warranty. Most solar installers give you a warranty of 20 to 25 years [4].

A brief calculation confirms how significant these savings can be.

For example: cutting $100 off your monthly energy bill translates to a savings of $24,000 within 20 years.

According to scientists from the United Kingdom, the potential of lowering energy bills is even higher. If houses could effectively store the solar energy generated throughout the day, energy bills could be reduced by more than 60 percent [6]. So, in the near future, we can expect even faster returns on investments.

Solar Renewable Energy Credits (SRECs) are another way to get the return on your investment faster. The system of SRECs measures the overall production of your photovoltaic solar panels in a year, and you receive one SREC for every 1,000 kilowatt hours generated by your array. The value of one SREC varies, but in some states can be up to $300 [7].

The difference between SRECs and Net Metering is that you are not selling energy to the grid; you are selling your consent that the energy company can claim your clean energy production as their own.

They do this to adhere to the Renewable Portfolio Standard, which requires that energy companies generate a portion of their electricity from renewable resources. Buying this portion from private solar owners is easier than re-structuring the company’s whole grid.

5. Energy security

You probably don’t realize this, but we depend on grid power for almost everything. And grid power is mainly generated by fossil fuels, a nonrenewable source of energy that is being depleted much more rapidly than most people think [9].

This means that our energy supply is susceptible to never-ending increases in energy prices.

When going solar, your energy supply will not be subject to international price fluctuations, and since no one can buy the sun’s energy to monopolize this resource, it is a very secure renewable energy source for the future.

6. Unlimited source of energy

The sun is the most abundant energy source available to our world, raining 173,000 terawatts of energy down on the Earth every second [14]. This energy can be harvested at any location globally, for as long as there is sunlight.

This is a major advantage because solar technology can provide power in the most remote locations on Earth. For example, the Australian Antarctic Division relies on solar energy to power their radio installations and automatic weather stations in Antarctica [11].

Innovations in technology also allow easier use of portable solar power sources. Perhaps the most extreme example is the use of solar energy to power space exploration. Even the Hubble Space Telescope is powered by its own solar array [12].

7. Wide variety of solar power applications in daily life

Electricity generation is not the only use of solar energy at home.

Solar water heaters are commonly used to heat and store hot water in warmer climates. They work by converting sunlight into energy for heating water through the use of a solar thermal collector. On sunny days, they can be very efficient in supplying enough hot water to cover a household’s warm water needs.

Other increasingly popular use of solar energy has been in powering our portable devices. The technology has advanced so far that we are able to charge our small electronics on the go. All we need is little bit of sunshine and a small solar panel that will either directly charge our mobile phone or will charge a battery bank where energy gets stored for later use.

But having power on the go is not the only advantage we get from this freely available source of energy.  

To our convenience, even outdoor electronic gadgets, like garden lights or home security systems, can be powered entirely from solar energy. This means that you can place these devices anywhere on your property and not worry about them switching off, since they get charged from their own solar panels.

Reolink Argus 2 solar-powered security camera

A great example is a solar-powered security camera Reolink Argus® 2 that demonstrates how easy it has become to install and use many of these smart devices without any professional help. This security camera can withstand bad weather, is wire-free and is powered from a solar panel that comes along with it. All it takes to set it up is to find a spot you want to monitor and make sure that you position the solar panel in the most sun-oriented angle. That’s it. Once this is done, you will have a perfectly functional home surveillance system, which is even eco-friendly and runs entirely from the sun’s energy.        

A couple more solar applications benefitting from the versatility of this energy source are also put into action when warming up swimming pools by using a solar cover to trap the heat from the sun or warming up water for outdoor showers. You can even prepare food on a solar cooker that generates heat of 300 degrees Fahrenheit just by turning the energy of light into heat and is a great option for outdoor cooking without burning fossil fuels or firewood.

8. Improving technology

Technological innovations in the solar power industry have advanced quickly over the last couple years. As photovoltaics research continues to make solar energy harvesting more efficient, the potential to transform solar power generation in the near future is incredible.

Just recently, a team of researchers at Technion – Israel Institute of Technology made a breakthrough in solar cell technology that could improve the efficiency of photovoltaic cells by approximately 70 percent.

Another great innovation came from scientists who have developed super-efficient solar cells capable of capturing 99.7 percent of light. These high-efficiency cells are called “super black,” and their forte is the ability to perform at almost the same rate of efficiency in cloudy conditions as in the perfect sunshine [8].

9. Increased value of your house

Solar installation is also a good investment because it adds value to your house. It is difficult to say an exact number, as the results depend on many factors, regarding the state of your property and solar system, but according to a study in California, 1 kilowatt of solar power increases the value of a house by more than $5,000 [13].

With increasing awareness on the benefits of renewable energy, more house buyers are interested in buying a property with a solar system in place.

10. The maintenance of solar systems is minimal

Solar panels are durable, and because there are no moving parts, there is very little risk of wear and tear. Most solar panels nowadays come with a 20 to 25-year warranty, and even though they are made from tempered glass, they can withstand even moderate hailstorms without any damage.

The most common maintenance is regular cleaning of dust and dirt particles because they could decrease efficiency in the long run.

11. Solar is environmentally friendly

Solar energy generation significantly reduces air pollution and greenhouse gas emissions.

In 2014, the total amount of emitted greenhouse gases in the United States dropped by 17 million metric tons thanks to the increase in solar installations (especially in California). Such a high potential for reducing greenhouse gas emissions is a promising step towards mitigating human impact on the global climate.

While the majority of other power plants, including renewable geothermal power plants, require water for cooling, solar farms need no water. This decreases water pollution and conserves local water resources for other uses such as drinking and irrigation.

A recent study carried out in England demonstrates that solar farms also have a positive impact on biodiversity.

12. Solar is good for our health

Improved air quality comes with great benefits to human health. Lower concentrations of sulfur, nitrogen, and particulate matter in the air we breathe can reduce the premature deaths of between 25,000 to 59,000 people, according to the U.S. Department of Energy [10].

Solar energy benefits human health

This number can be much higher if we take into consideration health problems caused by the impacts of climate change all over the world.

Some of these impacts are already visible in Bangladesh, which was hit by 70 climate-related natural disasters in the last 10 years, forcing hundreds of thousands people from rural areas to relocate.

13. Silent operation

Compared with the noisy generators and power plants of today’s world, solar panels are absolutely silent when working. And silence becomes very rare in our modern lives filled with sounds from all our devices and technology.

It has been found that noise pollution can negatively impact our own health and wellbeing. Researchers believe that noise can produce stress signals in the body, whether asleep or awake, and this can lead to a number of health issues, such as an increase in heart rate and blood pressure, and a hampering of the immune system.

Some symptoms of noise stress include inability to fall asleep, problems with concentration, and impaired communication. Long-term exposure to loud noises leads to anxiety and negatively impacts mental state.

Silent generation of energy is yet another positive attribute of solar power – even over other renewable energy options. As you may know, wind turbines or hydropower, for example, do not operate silently, they still produce some noise when in operation.

If you want to learn more about the benefits of solar energy, then check out The Benefits of Having Solar Panels.
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What are some disadvantages of solar energy?

1. High initial cost

Solar energy saves money in the long run, but one of the main disadvantages is the initial installation cost of the whole array, which could easily reach $15,000 or more.

Although solar power cuts off your monthly electricity bills instantly, the return on the investment comes after several years. This requires careful planning and a lot of research before deciding how to cover the upfront investment.

Luckily, there are a few options. You can choose from solar leases, loans, or power purchase agreements. Make sure you evaluate these options thoroughly before deciding whether photovoltaic solar panels are worth it.

2. Intermittent nature

The intermittent nature of solar energy is one of the main reasons why it is difficult to rely entirely on solar power at the moment. Solar energy is generated only from the sunlight. At night or on cloudy days, your system will not produce power.

When calculating how much power your solar system will produce, you have to take into consideration the weather patterns in your area and shorter periods of sunlight during winter months because both of these factors will decrease the amount of energy generated throughout the year.

3. Low efficiency of solar panels

One of the drawbacks of solar technology is the low efficiency of solar panels when converting the sun’s energy into electricity, meaning that a great deal of energy is lost in the process.

Most commercially available panels reach only 15 to 18 percent efficiency [15]. This means you need more panels to cover your energy needs, resulting in higher initial installation costs and a larger area to mount it.

Solar panels occupying all the roof space

Additionally, low efficiency can be further compromised by manmade dust particles deposited on solar panels. According to a recent study, solar panels in areas with heavy air pollution generate 25 percent less energy than expected. This happens because some pollutants from our industrial activities are sticky and tend to block the sunlight.

On the bright side, this technology is still improving, and new materials are being tested to tackle the issue of efficiency under different conditions.

4. Space and roof material requirements

An average 5-kilowatt installation for a family house might consist of 25 solar panels. Each panel is around 65 inches long and 40 inches wide. This means you need an area of 135 feet in length and 83 feet in width to place the whole solar system, which can be a problem for some houses.

Another issue when it comes to system placement is the suitability of the roofing material to hold the array. Older roofing materials that might need to be replaced in the next couple years are not a good option. Similarly, roofs with skylights or other built-in elements make the installation of a solar system difficult.

If you are unable to fit the array on your roof, there is also the option to use ground-mounted solar panels.

5. Expensive energy storage

Solar power is variable in its output, producing in excess during peak sunlight hours and shutting down completely at night. Solar batteries are able to solve this problem by charging during the day and providing power at night.

The downside of their use is the hefty price and maintenance, including replacement when needed. The most commonly used batteries at the moment are lithium-ion batteries, which can be stored both indoors and outdoors.

6. Environmental footprint of manufacture

Solar energy is labeled as clean energy because it has a lower environmental footprint than fossil fuels, but manufacturing solar panels still comes with environmental implications.

Solar cells are made of rare and toxic materials such as cadmium telluride or copper indium gallium selenide. The use of these elements could pose health risk for people and the environment if not handled properly. Financial incentives encourage prompt recycling of these materials [16].

Even the purification of the most commonly used solar cell material, silicon, requires the use of hazardous chemicals such as hydrogen fluoride, hydrochloric acid, or sulfuric acid [16].

Solar panels do not emit greenhouse gases when producing energy, but the processes prior their installation—including the extraction of their manufacturing materials and their transport—do. It is estimated that the amount of emissions produced throughout the lifetime of a solar system ranges between 0.07 to 0.18 pounds of CO2 per kilowatt-hour produced. Coal, by comparison, releases 1.4 to 3.6 pounds of CO2 per kilowatt-hour [16].  

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Solar energy currently has its disadvantages, but the majority of these downsides are technical in nature and likely to be overcome as technological innovation advances.

Along with other renewable sources such as geothermal energy, wind, and tidal power, solar energy is a promising alternative to more polluting forms of energy. Used together, renewables can take us toward a brighter, cleaner future.


References

[1] https://goo.gl/XzB18M
[2] http://www.solarpowereurope.org/wp-content/uploads/2018/09/Global-Market-Outlook-2018-2022.pdf
[3] https://goo.gl/V0AXZh
[4] https://goo.gl/RJezLo
[5] http://news.energysage.com/net-metering-and-srecs-explained/
[6] https://www.sciencedaily.com/releases/2017/08/170809073344.htm
[7] https://www.energysage.com/solar/cost-benefit/srecs-solar-renewable-energy-certificates/
[8] https://www.nrel.gov/news/press/2011/1671.html
[9] https://www.forbes.com/2009/07/24/peak-oil-production-business-energy-nelder.html
[10] https://www.sciencedaily.com/releases/2016/05/160518165257.htm
[11] https://goo.gl/ewUdMa
[12] http://www.esa.int/Our_Activities/Space_Engineering_Technology/How_Hubble_got_its_wings
[13] https://goo.gl/tHVNiR
[14] https://greentumble.com/what-are-the-environmental-benefits-of-solar-energy/
[15] https://understandsolar.com/solar-panel-output/
[16] https://goo.gl/hM3jZg