SOLAR ENERGY

Why solar energy?

Solar energy is considered a sustainable resource for several reasons:
• Solar energy is abundant and widely available, making it a reliable source of power for various applications [1] • Solar energy can be harnessed indefinitely without depleting the source [1] • Solar energy production does not emit greenhouse gases or other pollutants, making it a clean and sustainable alternative to traditional energy sources [1]

Solar energy has several advantages over other renewable energy sources, such as:
• Solar energy is an inexhaustible resource, as it is derived from the sun, which will continue to shine for billions of years [2] • Solar power can be utilized in various settings, from large-scale solar farms to small rooftop installations, making it a versatile energy source [3] • The cost of solar energy has decreased over the years, making it a more affordable option for many households and businesses. This has led to the widespread adoption of solar energy systems worldwide [1] • Continuous research and development in the field of solar energy have led to the creation of more efficient and cost-effective technologies, such as solar-plasma reactors for CO2 conversion [4] and solar-powered distillation and activated carbon treatment systems [1]

Solar energy technology

Solar energy technology has been improving rapidly, with innovations in solar power cells breaking key energy efficiency milestones. For example, multiple research groups have achieved 30% energy efficiency, and some multi-junction cells have reached efficiencies as high as 47%. These advancements can potentially increase the output of solar energy and accelerate the rollout of solar power. [5]

Solar energy technology involves the conversion of sunlight into usable energy for various applications, such as heating, cooling, and electricity generation. Three primary technologies for harnessing solar energy are PV, solar heating and cooling, and concentrating solar power [6].

Solar PV is a technology that converts sunlight directly into electricity using semiconductor materials, such as silicon, to generate an electric current. The process involves the absorption of photons from sunlight, which causes electrons to be knocked loose from their atoms, creating a flow of electricity. [7] Solar PV systems can be used for various residential, commercial, and industrial applications [8].

Solar heating and cooling use solar energy to heat and cool buildings and other spaces. It encompasses various systems such as photovoltaic solar energy, solar hot water/space heating, and solar seasonal storage. These technologies utilize the sun’s energy to provide heating during cold periods and cooling during warm periods, contributing to energy efficiency and sustainability. For example, solar thermal systems can capture and use a high proportion of solar radiation, offering sustainable and cost-effective solutions for heating and cooling [9, 10]. Additionally, the combination of solar thermal technology and heat pumps has been developed to heat houses and produce domestic hot water, further advancing the efficiency of these systems [11].

Concentrating Solar Power (CSP) is a technology that uses mirrors or lenses to concentrate a large area of sunlight onto a small area, which is then used to heat a fluid to produce steam and drive a turbine connected to an electrical generator [12]. This process is similar to that of traditional power plants, but instead of using fossil fuels, CSP plants rely on sunlight as the primary energy source [13]. CSP plants can also be equipped with thermal energy storage (TES) systems, which allow them to store excess heat generated during high solar radiation and release it during periods of low solar radiation or when electricity demand is high. This storage capability makes CSP plants more dispatchable and reduces their environmental impact by allowing them to operate more efficiently and with a lower dependence on grid electricity. [14]

Comparison of solar PV, solar heating and cooling, and CSP:

Solar PV	Solar heating and cooling	Concentrating Solar Power (CSP)
·  It can be installed on rooftops or in large-scale solar farms. ·  It has a high initial cost but low operating costs. ·  It requires minimal maintenance and has a long lifespan. ·  It can be combined with other renewable energy sources, such as wind or hydroelectric power, to create hybrid systems.	·  It can be used for both residential and commercial applications. ·  It requires a separate system for heating and cooling, which can increase the overall cost. ·  It may require additional energy sources, such as electricity or natural gas, for backup or during periods of low solar irradiance.	·  It requires large-scale installations, such as solar towers or troughs, to concentrate sunlight. ·  It has a higher initial cost than solar PV but can be more efficient in converting sunlight into electricity. ·  It requires a thermal energy storage system to ensure continuous operation during periods of low solar irradiance. ·  It can be combined with other renewable energy sources, such as wind or hydroelectric power, to create hybrid systems.

Challenges with Solar Energy

There are several challenges, issues, and impacts that need to be considered for the widespread adoption of solar energy, such as:
• Solar energy production is subject to temporary weather disruptions, such as cloudy days, which can reduce electricity generation. This intermittency affects the reliability of solar power, especially in certain geographic regions [15, 16].
• The supply and demand for solar energy are often mismatched, leading to challenges in energy storage and consumption. Sudden spikes in demand, such as in the morning and evening, do not always align with solar energy generation, requiring effective energy storage solutions [17].
• While solar energy is a clean and renewable source of energy, there are environmental concerns related to its production, such as the disposal of used solar panels and the associated pollution [16, 18].
• Utility-grade solar plants require large areas for solar panel installation, posing challenges in urban areas where space is limited. Additionally, the efficiency of solar panels and the associated costs of installation are areas of concern for the industry [16, 17] • The solar industry is also affected by economic and regulatory factors, such as the reliance on government programs and expiring tax incentives, which can impact the growth and demand for solar energy [16].

Solar energy in South East Asia

Solar energy is currently the cheapest renewable energy source, costing $23.52 per megawatt-hour (MWh). This is lower than the base cost of coal, which is $43.80 per MWh. The International Energy Agency (IEA) has reported that solar photovoltaics (PV) is cheaper than new coal- or gas-fired power plants in most countries, with 62% of solar PV projects being cheaper than the cheapest new fossil fuel. [19]

According to recent reports, solar energy is increasing in Southeast Asia, with the Southeast Asia Solar Energy Market expected to grow at a compound annual growth rate (CAGR) of 10.2% over the next five years [20]. Investments in renewables in Southeast Asia are expected to exceed US$76 billion from 2023-2025, with much of this expenditure driven by solar, wind, and geothermal investments [21].

The increase in solar energy in Southeast Asia can be attributed to several factors. One of the key reasons is the dramatic fall in the cost of solar photovoltaic technologies over the past decade, which has made solar energy more affordable and accessible. Additionally, the pursuit of solar energy is linked to projects of governance, social or moral reform, and expressions of care for distant others, which has led to a growing focus on solar energy in the region. These factors, combined with the global push for renewable energy sources, have contributed to the increasing adoption of solar energy in Southeast Asia. [22]

One notable example of a solar energy project in Southeast Asia is the 145MW floating photovoltaic solar power project built on 225 hectares of surface area on the Cirata Reservoir in West Java province, Indonesia. The Cirata Floating PV Power Plant will produce enough energy to power 50,000 homes and contribute to creating up to 800 jobs. Once completed, the project will be the largest of its kind in Southeast Asia and one of the largest in the world. [23]

By: Hendra WINASTU, SOLEN Principal Associate – IPC panel coordinator
Edited by: Nguyeng Duy Hung, SOLEN Director – IPC program director
Date: 21 January 2024
Article#: SOLEN-IPC-0032

Reference:
[1] Alman Sikder, M., & Ali, M.Y. Entry to the Stockholm Junior Water Prize 2023 Eco-Friendly and Cost-Effective Water Purification for Highly Polluted and Saline Sources Using Solar Powered Distillation and Activated Carbon.
[2] Enel Green Power. (2023). All the advantages of solar energy. Www.enelgreenpower.com. https://www.enelgreenpower.com/learning-hub/renewable-energies/solar-energy/advantages-solar-energy
[3] Comparison between Solar Energy Solutions and other Renewable sources of energy. (n.d.). Www.cleanmax.com. https://www.cleanmax.com/solar-update/how-solar-energy-compares-to-other-renewable-sources-of-energy.php
[4] Trelles, J.P. (2021). Solar-plasma reactors for CO2 conversion. Journal of Physics D: Applied Physics, 55.
[5] Carrington, D. (2023, July 6). “Revolutionary” solar power cell innovations break key energy threshold. The Guardian. https://www.theguardian.com/environment/2023/jul/06/revolutionary-solar-power-cell-innovations-break-key-energy-threshold
[6] SEIA. (2020). Solar Technologies | SEIA. SEIA. https://www.seia.org/initiatives/solar-technologies
[7] Agyenim-Boateng, K., & Boehm, R.F. (2011). Impact of Storage Integrated Solar Photovoltaics (PV) Power System on Utility Peak Loads.
[8] Holzhey, P., Prettl, M., Collavini, S., Chang, N., & Saliba, M. (2023). Towards Commercialisation with Lightweight, Flexible Perovskite Solar Cells for Residential Photovoltaics. 2023 IEEE 50th Photovoltaic Specialists Conference (PVSC), 1-1.
[9] Eaton, D.J., McGarity, A.E., & Rogers, R.L. (1983). Is it worthwhile to invest in small scale solar heating.
[10] Braga, F.S. (2016). Leadership in Sustainable Agribusiness, Innovation, and Solar Thermal Renewable Energy: Opportunities for Sustainable Agribusiness. International Journal on Food System Dynamics, 7, 143-182.
[11] Hadorn, J. (2010). Solar and Heat Pump Systems – IEA SHC Task 44 & HPP.
[12] Alami, A.H., Olabi, A.G., Mdallal, A., Rezk, A., Radwan, A., Rahman, S.M., Shah, S.K., & Abdelkareem, M.A. (2023). Concentrating solar power (CSP) technologies: Status and analysis. International Journal of Thermofluids.
[13] Islam, M. T., Huda, N., Abdullah, A. B., & Saidur, R. (2018). A comprehensive review of state-of-the-art concentrating solar power (CSP) technologies: Current status and research trends. Renewable and Sustainable Energy Reviews, 91, 987–1018. https://doi.org/10.1016/j.rser.2018.04.097
[14] Gasa, G., Lopez-Roman, A., Prieto, C., & Cabeza, L. F. (2021). Life Cycle Assessment (LCA) of a Concentrating Solar Power (CSP) Plant in Tower Configuration with and without Thermal Energy Storage (TES). Sustainability, 13(7), 3672. https://doi.org/10.3390/su13073672
[15] Constellation. (2023). The Advantages and Disadvantages of Solar Energy. Www.constellation.com; Constellation. https://www.constellation.com/energy-101/energy-innovation/solar-energy-pros-and-cons.html
[16] Challenges Facing The Solar Industry Right Now. (2021, April 28). Dataforma. https://www.dataforma.com/challenges-facing-the-solar-industry-right-now/
[17] The Challenges of Solar Energy. (n.d.). Www.fuergy.com. https://www.fuergy.com/blog/the-challenges-of-solar-energy
[18] Atasu, A., Duran, S., & Van Wassenhove, L. N. (2021, June 18). The Dark Side of Solar Power. Harvard Business Review. https://hbr.org/2021/06/the-dark-side-of-solar-power
[19] . Timmerberg, S., Sanna, A., Kaltschmitt, M., & Finkbeiner, M. (2019). Renewable electricity targets in selected MENA countries – Assessment of available resources, generation costs and GHG emissions. Energy Reports, 5, 1470–1487. https://doi.org/10.1016/j.egyr.2019.10.003
[20] Southeast Asia Solar Energy Market | 2022 – 27 | Industry Share, Size, Growth – Mordor Intelligence. (n.d.). Www.mordorintelligence.com. https://www.mordorintelligence.com/industry-reports/southeast-asia-solar-energy-market
[21] Yuen, S. (2023, October 19). Solar in Southeast Asia: what’s happening in the market? PV Tech. https://www.pv-tech.org/solar-in-southeast-asia-whats-happening-in-the-market/
[22] Cross, J. (2019). The solar good: energy ethics in poor markets. Journal of the Royal Anthropological Institute.
[23] Baker, D. (n.d.). Solar energy in Asia: top projects, jobs, and market trends. Www.airswift.com. https://www.airswift.com/blog/solar-energy-asia