24 Sep 2023  |   06:03am IST

Foldable and Portable Solar Panels: a boon for rural areas

Sridhar D Iyer

Power play: Of the total power generation in India, 75% is from coal thermal power plants. We also depend on hydroelectricity and nuclear plants that provide electricity of varying capacities. Yet, every State faces a shortage of electricity due to an increase in population, houses, offices, industries, shops, pilferage, outages and frequent load-shedding. Since energy is critical for people and for India’s economic progress, decades back there was less resistance to power projects, but in recent years there are environmental laws and resistance from activists, which lead to delays or even closure of the projects. 

The International Energy Agency (IEA) reported that in the next 20 years, India would see the largest demand and increase in energy. The Ministry for New and Renewable Energy (MNRE) was founded to study the feasibility and speed up the implementation of various RE sources such as solar, wind, tidal, wave and ocean thermal energy conversion. Of all these, solar energy is the simplest, cleanest and most economical. 

Being in the tropics, India obtains ample sunlight throughout the year and of high intensity radiations somewhere or the other in the country. In the past, we could not significantly harness solar energy because of lack of technology, production and availability of photovoltaic (PV cells), installation cost, scarcity of trained people and easily obtainable electricity from the grids. 

Since the MNRE urges the use of solar power, several States have guidelines and mandates to set-up solar panels and offer subsidies. The initial cost of installation may be high but within a few months or years it is recovered as there are no electricity bills to be paid and by selling the excess energy to the governments. In 2015, the Kochi airport (Kerala) was the first to run all its operation solely on solar energy. The newly built Mopa airport (Goa) has a 5 MW solar plant.

Goa’s electricity department distributes 720 MW by purchasing at various rates from Maharashtra and Karnataka and solar power from Assam and Arunachal Pradesh. But with increasing population and associated needs, the power supply would be insufficient. It is projected that by 2030, Goa would need over 1,000 MW of power. 

Methods to tap solar energy: Solar energy can be tapped by three types of panels: roof or ground mounted, floating, and folding and portable. Rooftop or ground-mounted panels are common while Floating Solar Panels (FSP) are in water bodies such as dams, reservoirs, and lakes. The FSP are cost-effective, no worries of land acquisition and obtained electrical supply can be connected to main grids. Three FSP are operational in: Telangana (100 megawatts (MW)); Andhra Pradesh (25 MW) and Kerala (92 MW). The upcoming FSP are in: Jharkhand (100 MW), Madhya Pradesh (600 MW, largest in the world), Uttar Pradesh (150 MW), and a combined ground and FSP in Gujarat (15 MW). Goa has planned FSP in Amthane, Anjunem, Panchwai, Chapoli and Selaulim dams. Though Goa government encourages use of solar energy but the response is poor. 

Foldable and Portable Solar Panels (FPSP)

The typical solar installations and FPSP cater to urban and to limited rural areas. Problems arise in remote areas where there are no large settlements but solar power is needed for houses, schools, district hospitals etc, as grid supply may or may not exist. In such areas, FPSP could be provided. The FPSP varies from 10-W to 100-W and consequently the number of panels will also differ. For example, for a 1 KW system, 10 PV panels of 100-W each will be needed. 

Solar panels come in sizes such as 165 x 99 cm or 195.5 x 99 cm. Mini solar panels of 1.5 x 6.4 cm to 22.5 x 12.7 cm can generate between 0.06 and 4-W. Mini panels are sufficient for low power applications. 

Advantages: The FPSP have several advantages, are versatile, can be connected to portable solar generators and storage batteries. Most FPSP are small and water resistant while waterproof models are better since Goa witnesses’ heavy monsoons. The FPSP require little maintenance, frequent cleaning is not needed, can be carried in a backpack or suitcase and used wherever there is direct sunlight. Depending on the wattage, the FPSP can charge laptops, mobile phones, batteries, power banks, torchlights, smart watches and even used for fans, lights, CCTV etc and can be used during camping, hiking and trekking.

Prices and Warranty: Monocrystalline panels cost between Rs 270 and Rs 3,300 while polycrystalline panels cost between Rs 230 and Rs 2,300. The lower prices are for the 10-W panels and is ten-fold for the 100-W panels. The FPSP has two to five years warranty on manufacturing defects and five to 15 years for output performance.

Uses of FPSP: Three years back the world was under the grip of the Covid-19 pandemic and Goa was no exception. Schools and colleges were closed for months and on-line classes were a challenge for teachers, students and parents. But students in several interior dwelling villages either had no smart phones, laptops, mobile connectivity, electricity or all of these. 

Erratic supply and failure of electricity still haunt schools and households in remote villages. The problem could be resolved by installing rooftop or ground-mounted panels in schools and the villagers trained to maintain the panels. At schools, FPSP could be used to generate energy for fans, lights, computers, overhead projectors, laboratory equipment etc. Solar energy would be beneficial to students and teachers, attendance would increase and quality of education would improve.  

Based on their energy requirements, schools can procure one or more FPSP since the sizes and prices are not prohibitive. The money could come largely from the government under its various developmental programmes, as a one-time minor contribution by parents and teachers, crowd funding, and from corporate social responsibility funds. 

Goa could learn from Modhera (Gujarat) which is India’s first solar powered village. The villagers maintain and clean the panels and government purchases the excess power produced. Goa could successfully implement such a project and provide FPSP to hinterland villages. The government could save money on laying overhead and/or under-ground cables, erecting pylons, maintenance and repairs of transformers and so forth.  

Considering the global reduction in fossil fuels, low probability of discovering new deposits of oil and gas, rising cost, and environmental concerns; we need to use solar power to the maximum extent by the above three methods. India could be a top consumer and producer of solar power and realise the 300 GW solar energy by 2030 as assured by the Centre during the Glasgow climate summit. Let us make energy while the selfless sun is shining brightly!

(The author is a Marine Geologist, Chief Scientist (retired), CSIR-NIO, Dona Paula, Goa)

IDhar UDHAR

Iddhar Udhar