A photovoltaic cell or solar cell is an electrical device made of materials that can convert light directly to electricity. These electrical devices are assembled in a module to collectively form a photovoltaic solar panel.
Because solar cells and solar panels can generate electricity directly from sunlight, they have been positioned as critical materials and equipment for promoting alternative energy through solar power. Note that photovoltaic solar power is a direct type solar power. On the other hand, concentrated solar power is an indirect type.
Pros: The Benefits and Advantages of Solar Panels
1. Self-Sustaining Source of Energy
One of the advantages of solar panels is that beyond installation and maintenance, the energy they produce or electricity they generate is relatively free. Note that it is also a continuous source of energy. A home or building, as well as a community installed with solar panels can be self-sustaining. There is no need to pay electricity distributors. Furthermore, it is also important to highlight the fact that unlike fossil fuel or nuclear power, materials do not have to be continuously extracted, processed, and transported.
2. Almost Zero Pollution and Emission
From the consumption side, the energy produced by a solar panel does not result in the emission of greenhouse gasses. Of course, the production of photovoltaic cells and solar panels include raw material extractions and energy inputs from unclean sources of energy, such as fossil fuels. However, a 2008 study by Vasilis. M. Fthenakis, Hyung Chul Kim, and Erik Alsema revealed that solar panels produce far less lifecycle air emissions per GWh than conventional electricity generation based on fossil fuels. A further assessment concluded that at least 89 percent of emissions associated with electricity generation could be prevented if photovoltaic displaces fossil fuels and other unclean sources of energy.
3. Relatively Cost Effective
Another benefit or advantage of solar panels is that their installation and usage have become cost effective and efficient. The price of these panels has continued to decline due to grid parity. In some countries, electricity generation through solar power is cheaper than reliance on fossil fuel electricity from the electricity grid. Advancements in production and current demand have also driven down manufacturing costs. It is also worth reiterating that solar power via solar panel can be a self-sustaining source of energy that does not require distribution costs and cyclical production processes. Furthermore, because solar energy is free and unlimited, solar power is immune to price volatility that typically characterizes fossil fuels and nuclear power.
4. Decentralization and Going Off the Grid
Similar to advantages such as self-sustenance and cost-effectiveness, the widespread deployment of solar panels can promote self-reliant communities that are not dependent on electricity distributors, energy producers, and the entire energy markets. Decentralization due to self-reliance drives down the costs of electricity. Note that generating electricity from fossil fuels and nuclear power have myriad of costs associated with transportation and distribution. Also, because solar panels can work off the grid, it has significant benefits for people living in rural areas or isolated communities.
5. Promises Due to Technological Progress
Some of the notable criticisms of solar panels include production costs and inefficiency. However, ongoing developments in technology, including manufacturing procedures, improvements in the factors of production, and the discovery of novel solar cell materials, could supersede these limitations in the future. Investments in research and development due to expressed interest of energy companies and governments to build alternative energy capacities are driving the progress further.
Cons: The Limitations and Disadvantages of Solar Panels
1. Intermittency of Solar Energy
The energy coming from the sun might be relatively infinite, but it is not 100 percent exploitable. Photovoltaic cells can only convert around 20 to 30 percent of solar energy into electricity. Increasing electricity generation capacity requires increasing the number of solar cells and solar panels in a given area. Furthermore, solar panels do not work at night and weather conditions and seasons affect their efficiency. Electricity generation capacity naturally drops during the winter season or typhoon months when there are fewer sunlight hours and radiation from the sun is less intense.
2. Dependence on Battery Technology
Another disadvantage of solar panels centers again on the intermittency of solar energy. Note that storage using battery packs is an integral component of a solar power system based on solar panels. Storage is essential because solar energy is intermittent. However, a report by Vaclab Smil published in IEEE Spectrum noted that battery capacities need to be bigger and more efficient for solar power to get a stronghold. A study by Guilherme de Oliveira e Silva and Patrick Hendrick also revealed that while solar panels can cover up to 40 percent of the electricity needs of a typical household, going beyond this level would require the use of more lithium-ion batteries that are currently expensive.
3. Requires Use of Expansive Areas
Higher electricity generation capacity using solar panels requires larger areas. A report from the U.S. National Renewable Energy Laboratory mentioned that generating 1 GW per year requires an average of 2.8 acres of land covered by solar panels. Hence, providing electricity for 1000 households would require 32 acres of land. The reliance on expansive land areas is a remarkable limitation of solar panels because it triggers concerns over land use prioritization. Some might argue that such large tracks of lands are better off for residential areas or agricultural purposes.
4. It Still Has a Carbon Footprint
Remember that solar power has zero emission when considering only the consumption side. But it is not an absolute emission-free technology as mentioned in the study of Fthenakis et al. A meta-survey by Daniel Nugent and Benjamin K. Sovacool specifically revealed that materials extraction, manufacturing, installation and usage, and disposal and decommissioning are activities in the entire lifecycle of a solar panel that require energy inputs from hydrocarbons, thus resulting in greenhouse gas emissions. However, this study also concluded that analyzing these activities and lifecycle stages can help in finding ways to lower the carbon footprint of solar panels.
FURTHER READINGS AND REFERENCES
- De Oliveira e Silva, G. and Hendrick, P. 2017. “Photovoltaic Self-Sufficiency of Belgian Households Using Lithium-Ion Batteries, and its Impact on the Grid.” Applied Energy. 195(1): 786-799. DOI: 10.1016/j.apenergy.2017.03.112
- Fthenakis, V. M., Kim, H. C., and Alsema, E. 2008. “Emissions from Photovoltaic Life Cycles.” Environmental Science and Technology. 42(6): 2168-2174. DOI: 10.1021/es071763q
- Nugent, D. and Sovacool, B. K. 2014. “Assessing the Lifecycle Greenhouse Gas Emissions from Solar PV and Wind Energy: A Critical Meta-Survey.” Energy Policy. 65: 229-244. DOI: 10.1016/j.enpol.2013.10.048
- Ong, S., Campbell, C., Denholm, P, Margolis, R., and Heath, G. 2013. Land-Use Requirements for Solar Power Plants in the United States. National Renewable Energy Laboratory
- Smil, V. 2016. “Batteries Need to Be Bigger—Like, Enormous—For Solar Power to Shine.” IEEE Spectrum. Available online