The Pros and Cons of Using Solar Energy

Is solar energy actually good?

Amidst all the discussions about using renewable sources of energy such as wind or solar power to save the environment, there is also a school of thought that highlights the drawbacks of using solar energy.

Although the overall consumption of solar energy for electricity is 2.8% currently, the international organizations and even the Conference of the Paris 24 or COP 24 are continually pushing towards increasing it. The current target is to increase this consumption to 32% worldwide by the year 2030.

It cannot be denied that the sun offers one of the most abundant sources of energy. Estimates show that our earth receives around 120,000 Terawatts of solar irradiation, which is 20,000 times more power than what our world actually needs.

If we manage to use this energy efficiently, we might not have to worry about the depleting oil, coal, and natural gas reserves to satisfy our energy needs. There are many ways in which solar energy is captured and used as a renewable source to make energy usage cleaner and transition to a low-carbon economy.

However, some people have concerns regarding the usage of solar power. This article talks about all the solar energy pros and cons.

Advantages of using solar energy

Let’s begin by talking about some advantages of using solar power as an energy source!

Clean energy source

Using solar energy gives you a clean source that does not contaminate the environment. It is a renewable energy source and can be harnessed directly from the sun daily.

Hence, there are no chances of running out of it as long as the sun does not die. According to the scientists, that would happen at least after 5 billion years, so we are safe to use solar power for an ample amount of time.

Mitigate climate change effects

Embracing solar power has direct benefits in reducing our carbon footprints on the planet. Estimates show that adopting solar will help in lowering future climate change damages, saving $259 billion globally.

Incentives from the governments

Most governments are giving incentives to people who are installing solar panels in their homes. There are many government subsidies that you can avail simply by using solar power to get most of your energy requirements fulfilled for everyday use.

Reduces your electricity bills

Your electricity bills can also reduce immensely if you supplement your regular electricity with solar power. Moreover, with increasing technological advancements in the technology of solar panels, there are also possibilities of sharing the extra power with your neighbors or the electricity board of your neighborhood.

In return, you get paid for it or get a rebate on your next bill. Hence, the return on investment is very high when you install solar panels to use solar energy.

Cost of maintenance is low

Moreover, the maintenance cost of a solar panel is meager. So, once you install it in your house, you are in the right place for the next 10-20 years depending on the quality.

Suppliers of solar panels also give long-lasting warranties on these panels so you can always get in touch with them in case of a problem. Also, these panels need to be cleaned a few times a year.

So, you can either do it yourself or hire a cleaning company to do it for you.

Disadvantages of solar energy

While the advantages of using solar power look promising, there are some disadvantages too. Let’s discuss them in more detail.

Installation associated with pollution

Although when we think of solar power, we think of clean energy, it is essential to note that the installation of solar panels is also associated with pollution. When solar panels are transported and are installed, they tend to emit greenhouse gases.

Moreover, some of the materials used in photovoltaic systems are toxic. So, it can indirectly affect the environment.

High initial cost

The initial cost of solar installation and usage is very high because the person has to pay for the entire package. The whole system has batteries, wiring, solar panels, and inverters.

However, the technology in this sector is developing with every passing day, so there is an excellent likelihood of a reduction in costs soon.

Depends on the weather

Using solar power is much dependent on the sun. So, if the weather is cloudy with no sun, you might not get any electricity that day.

Since the storage technology is not that advanced at the moment, solar panels cannot store a lot of energy.

Therefore, a 100% reliance on solar energy is not possible at the moment. You must supplement it with traditional energy sources.

From the above account, we can see that solar energy is not as clean as we thought. It also has some disadvantages associated with it.

The biggest one is the fact that it also emits greenhouse gases which is harmful to the environment. However, if it is seen in the relative sense and compared to the current sources, the pollution created by solar panels is somewhat less.

Some other cons such as high costs and weather dependence do cause some skepticism. But the reduction in electricity bills, subsidies, and low maintenance costs do compensate for it.

Conclusion

Solar power is readily available to us in abundance. Most governments, major companies, and international organizations are taking proper efforts at their end to make it work.

As more investments pour in to develop innovative solutions to capture solar energy, we will likely be able to use this abundant source of energy more efficiently. However, it is also important to develop new ways to deal with rising solar waste and make solar panels recyclable.

Despite the criticism and the toxic waste these solar panels produce, we know for the fact that solar power is a much more optimal resource than fossil fuels.

So, which school of thought do you belong to?

Иностранный язык (английский яз)

Технический текст «How Solar Energy Works»

Solar energy – power from the sun – is free and inexhaustible. This vast, clean energy resource represents a viable alternative to the fossil fuels that currently pollute our air and water, threaten our public health, and contribute to global warming. Failing to take ad­vantage of such a widely available and low- impact resource would be a grave injustice to our children and all future generations.

In the broadest sense, solar energy supports all life on Earth and is the basis for almost every form of energy we use. The sun makes plants grow, which can be burned as «biomass» fuel or, if left to rot in swamps and compressed underground for millions of years, in the form of coal and oil. Heat from the sun causes tem­perature differences between areas, producing wind that can power turbines. Water evaporates because of the sun, falls on high eleva­tions, and rushes down to the sea, spinning hydroelectric turbines as it passes. But solar energy usually refers to ways the sun’s ener­gy can be used to directly generate heat, lighting, and electricity

The solar resource. The amount of energy from the sun that falls on Earth’s surface is enormous. All the energy stored in Earth’s reserves of coal, oil, and natural gas is matched by the energy from just 20 days of sunshine. Outside Earth’s atmosphere, the sun’s en­ergy contains about 1,300 watts per square meter. About one third of this light is reflected back into space, and some is absorbed by the atmosphere (in part causing winds to blow).

By the time it reaches Earth’s surface, the energy in sunlight has fallen to about 1,000 watts per square meter at noon on a cloud­less day. Averaged over the entire surface of the planet, 24 hours per day for a year, each square meter collects the approximate en­ergy equivalent of almost a barrel of oil each year, or 4,2 kilowatt hours of energy every day.

This figure varies by location and weather patterns. Deserts, with very dry air and little cloud cover, receive the most sun more than six kilowatt hours per day per square meter. Northern climes get closer lo 3.6 kilowatt hours.

Passive solar design for buildings. One simple, obvious use of sunlight is to light our buildings. If properly designed, buildings can capture the sun’s heat in the winter and minimize it in the summer, while using daylight year round. Buildings designed in such a way are utilizing passive solar energy a resource that can be tapped with­out mechanical means to help heat, cool, or light a building. South facing windows, skylights, awnings, and shade trees with the sun in mind can be comfortable and beautiful places to live and work.

Solar heat collectors. Besides using design features to maxi­mize their use of the sun, some buildings have systems that actively gather and store solar energy. Solar collectors, for example, sit on the rooftops of buildings to collect solar energy for space heating, water heating, and space cooling. Most are large, flat boxes painted black on the inside and covered with glass. In the most common design, pipes in the box carry liquids that transfer the heat from the box into the building. This heated liquid usually a water alcohol mixture to prevent freezing is used to heat water in a tank or is passed through radiators that heat the air. Oddly enough, solar heat can also power a cooling system. Today, about 1,5 million U.S. homes and businesses use solar water heaters. In other countries, solar collectors are much more common; Israel requires all new homes and apartments to use solar water heating, and 92 percent of the existing homes in Cyprus already have solar water heaters. With natural gas prices at historically high levels, solar water and space heaters have become much more economic.

The future of solar energy. Solar energy technologies poised for significant growth in the 21st century. More and more architects and contractors are recognizing the value of passive solar and learning how to effectively incorporate it into building designs. Solar hot water systems can compete economically conventional systems in some areas. And as the cost of solar PV continues to decline, these systems will penetrate increasingly larger markets. In fact, the solar PV industry aims to provide all new U.S. electricity generation by 2025.

Aggressive financial incentives in Germany and Japan have made these countries global leaders in solar deployment for years.

1. Try to memorize the following words and phrases.

How can we store more energy from the sun and the wind?

By Daniel Thomas
Business reporter

4 December 2015

It could be a scene from a science fiction movie.

Deep in the Nevada desert, thousands of mirrors arrayed in concentric circles face the sky, lit up by the sun.

All this reflected sunshine is directed to the top of a 640 ft (195m) tower standing in their midst.

It’s an innovative power plant generating electricity, but not in a way you might expect. And it can carry on doing so even after the sun goes down.

The concentrated light heats up liquid salt pumped to the top of the tower — the temperature reaches 566C (1,050F) — and this heat is then used to make steam to power an electricity generator in another part of the plant.

«The issue with solar traditionally is it is an intermittent power source — you can only produce electricity when the sun is shining,» explains Kevin Smith, whose company Solar Reserve built the Crescent Dunes plant.

«But because we store the energy as heat, we can reliably produce electricity 24 hours a day, just like a conventional gas fired power station.»

Growing market

The plant is one of a raft of sustainable energy storage solutions trying to address renewable energy’s Achilles heel: its variability — ignoring tidal power’s constancy.

If we could store the electricity that sun and wind produce, we could tap into those stores when production dips.

And this is the only way we’re going to mount an effective challenge to the dominance of fossil fuels, experts say. Yes, tidal power is renewable and constant, but as yet, we haven’t found commercially viable ways of tapping into it.

Storage methods currently being used around the world include batteries, flywheels, geothermal plants, compressed air and hydrogen — even ice. But the the most popular method is hydro power — water pumped to the top of a mountain and then released to power turbines at the bottom.

According to research company Navigant, global energy storage installations are going to rise from about 1,750 megawatts (MW) in 2016 to nearly 11,000 MW by 2020.

«We are moving away from very large conventional power stations that produce electricity which is sent through the grid to consumers, to a system where power is produced in a much more distributed way,» says IHS’s Sam Wilkinson.

«So storage is obviously a major focus, because it allows you to compensate for and correct for a lot of that fluctuating generation that comes from renewables.»

Power to the people

Our homes are increasingly being used for energy storage as well.

Tesla’s Powerwall, announced earlier this year, is just one of a crop of new storage batteries designed for domestic use.

The US electric car manufacturer points out that the average household uses more electricity in the morning and evening than during the day, when solar energy is plentiful. So its battery charges during the day from solar roof panels, then powers the home in the evening.

«Without a home battery, excess solar energy is often sold to the power company and purchased back in the evening [at a higher price],» Tesla argues.

«The mismatch adds demand on power plants and increases carbon emissions,» it adds.

The same principle is being applied at a new housing development in Hoog Dalem, the Netherlands — part of the Universal Smart Energy Framework project being rolled out by a consortium of companies, including ABB, IBM and Stedin.

Solar-panelled homes are equipped with batteries to store the energy produced during the day for use when the sun goes down.

Used in conjunction with smart meters — which help businesses and domestic users manage electricity use more efficiently — home batteries could revolutionise the way we consume energy, proponents argue.

‘Three tennis courts’

Larger battery plants such as Smarter Network Storage (SNS) in Leighton Buzzard, UK, are also likely to play a big role.

The plant comprises 50,000 lithium-ion battery cells, across a site the size of three tennis courts. It can store enough energy to power 1,100 typical UK homes for a day during times of average demand.

Nick Heyward, who manages the UK Power Networks project, explains that our electricity grids need to balance supply and demand at all times, but they are struggling to cope as more wind and solar power comes online.

«One solution could be to add capacity to the existing grid, but that could be very expensive and disruptive,» he says. «And then you have the problem of energy curtailment — where wind and solar plants are switched off when there isn’t much demand, which is a waste.»

Storage systems like SNS offer the ability to export energy to the grid at times of high demand, and keep it in reserve when demand is low.

Mr Heyward believes that if such plants were replicated across the UK, it could unlock more than ВЈ600m ($895m) of benefits annually by 2040.

Green but unclean?

But environmentalists are concerned that many of the constituents in the conventional battery, such as cobalt and nickel, are pollutants. So the race is on to find cleaner alternatives.

Aquion’s saltwater and manganese oxide battery is made from more sustainable materials than the typical lithium-ion battery, tolerates more charge and discharge cycles, costs less, and doesn’t catch fire, the company maintains.

Ambri, meanwhile, has developed a liquid metal battery, which it says is low-cost and emissions free. It also says its liquid electrodes are stronger than the solid ones found in common batteries, and thus less susceptible to failure.

While such innovations may be welcome, the fact remains that the US still derives the vast majority of its electrical storage from pumped hydro — which is not one of the most efficient energy storage technologies.

The number of projects in the pipeline bodes well, says the Energy Storage Association, but we are still a long way from the storage levels we need.

One big impediment is regulation — or lack of it. Governments around the world are only now beginning to respond to this new energy landscape.