From the time of Industrial Revolution in the 18th century, fossil fuels came to forefront as the primary source of energy to cater to the ever increasing demand. Petroleum, natural gas and coal constitute the primary fossil fuels. Easy availability of coal closer to the surface of the earth, its ability to be used without any further processing positioned coal as the best candidate for producing electricity, power railroads, steam engines, and even ships. This was followed by the petroleum revolution in the 19th century. Fossil fuels have made significant contributions to the global economy though it is being looked upon as a villain of peace in the 21st century. However, it is also true that enormous amounts of fossil fuels burnt over centuries have created severe impacts on the earth’s atmosphere. In turn, this has compelled global leaders to sit up and take stock. According to Euro Solar Global, they have now found the answer in renewable energy in the form of solar power, and wind power to lead the next round of global energy revolution.
The sun is a huge source of sustainable clean energy without the toxic pollution from fossil fuels impacting global warming. In this article, we examine the various beneficial impact of solar energy on global warming and how this perennial source of energy can influence factors that affect climate change.
Thermal plants are also known as CSP (Concentrating Solar thermal power stations) and PV or Photovoltaic cell based solar power systems constitute two broad categories under solar energy. Environmental impact in both the systems can vary significantly depending on the technology employed. Habitat loss, water use, land use and hazardous material used in manufacturing are among the major areas of concern. Another important factor is the scale ranging from the small rooftop solar panels to larger scale CSP and PV projects.
Land use/habitat loss
For the large scale solar projects, location is a major factor that could influence habitat loss and land degradation. The area of land required would also vary depending on the technology employed, topography and intensity of sun rays. About 4 to 10 acres is the estimated area requirement for a utility scale solar system based on PV cells to generate 1 MW of electrical energy. In the case of CSP, the area requirement can go right up to 16.5 acres for every MW that is produced.
Wind farms have the opportunity to share the land for agricultural use, but solar projects have lesser opportunities in this direction. However, land use concerns can be minimised or eliminated by identifying low-quality locations like abandoned mining sites, Brownfield, existing transmission/transportation corridors, etc. Smaller systems built on rooftops too will have minimal impact on land use.
The PV based solar cells need no water for generating electrical energy. However, some amount of water is utilised in the manufacturing process of various PV components.
On the other hand, the CSP plants do need water for the purpose of cooling, as with other thermal electricity generating plants. The cooling system employed location of the plant and plant design will determine the quantum of water used. CSP plants using wet-recirculation technology combined with cooling towers draw about 650 gallons water for every megawatt of electricity produced. CSP plants using other cooling technologies do bring more water though the overall water consumption pegs lower in the absence of water lost in the form of steam. Although dry cooling is an option for the CSP plants, it is not a viable solution.
Given that Australia receives the most sunshine in a year, there is vast potential to tap this never ending source of energy for domestic as well as commercial use. Once this happens, scarce water that is used in thermal power production can also find use in other areas like agricultural production. The transition can bring multiple benefits like increased agricultural production, reduced carbon footprint from coal-based power generation and above all, a cleaner environment for the population.
The process of making solar PV cell includes several hazardous materials, and most of them are used for purifying and cleaning the surface of the semiconductor. These are the same chemicals used by the semiconductor industry and include sulphuric acid, hydrochloric acid, hydrogen fluoride, nitric acid, acetone and trichloroethane. While the quantum and type of chemicals used vary depending on various factors, workers do face certain associated health risks. Disposing of these harmful wastes is, therefore, a concern associated with the proliferation of solar power systems.
Technological advances have also brought into focus thin-film photovoltaic cells that carry more toxic material significantly compared to the traditional PV cells. Thankfully manufacturers enjoy a significant financial incentive in recycling these materials since they are expensive and some of them even rare. Any residual waste needs careful handling in the interest of public health and environmental concerns.
Global Warming Emission and how solar energy reduces greenhouse gases
Although global warming emission is absent in the production of solar energy, other stages involved in the life-cycle of solar systems including transportation of materials, manufacturing, maintenance, installation and decommissioning does require a certain amount of emissions. However, most of these emissions are in the range of 0.07 to 0.18 pound of CO2 equivalent for every kW of power produced. In the case of CSP, this range moves to 0.08 to 0.2 pounds. In both instances, these emissions are significantly lower compared to 0.6 to 2 pounds per kWh in the case of gas-based electricity production and 1.4 to 3.6 pounds per kWh in the event of coal-based power production.
How do solar panels reduce greenhouse gases
Solar energy produced with the help of solar panels significantly contributes to the reduction of greenhouse gases in our atmosphere. The cause of climate change is greenhouse gases, and when we overload the environment with these emissions, they, in turn, cause a steady rise in the earth’s temperature. The consequences are not limited to climate change alone, but also impact our health adversely.
The continuing supply of raw material (sun rays) free of cost, and the clean energy derived from the sun make a strong case for further proliferation of solar systems around the globe. Every individual and business can make stellar contributions towards reducing global warming and thereby help the cause of climate change by adopting solar energy as the primary source of all energy needs.