Felicia Cruz, Hanna el Debbar, Jodel Fernandez, Daenne Gomez, Mark Tan, Benny Tañedo, and Chad Yee
Scientists are always on the go; there is a constant demand for coming up with fresh takes on environment-friendly technologies. Our resources, after all, can only last for so long. As of late, there have been avenues sprouting with new and “green” ideas, though among them, the use of solar cells is perhaps one of the most common today.
Harnessing energy from the sun isn’t a new concept to us. Solar panels are present in many places today, even in the Philippines. We can see them on posts along highways and in schools, on the roofs of houses and of some institutions. They’re used to power cellphone chargers, cars, and even planes.
Aside from the examples mentioned, solar energy is also used to address irrigation problems and increase water access in certain areas through the use of solar-powered pumps.
A solar pump usually has three main components: The solar panels, the wiring, and a pump.
As you may know, the solar panels are there to collect energy from sunlight. When rays strike the panels, their electrons dislodge and—to put it simply—they go crazy. This allows for the production of direct-current electricity.
Silicon and other semiconductors coating the panels enable electron movement and electricity production. The electricity flows through the wiring until it finally reaches the pump. The pump is then powered and is used for the circulation of water.
Because the pump is reliant on solar energy, you may be thinking, what if there are thick clouds blocking the sun? What if there’s just really not enough sunlight? Does that mean people would have to go back to walking long distances just to fetch water?
Not necessarily. First of all, having some clouds won’t completely stop solar panels from collecting energy. However, electricity production (and energy collection, of course) may be diminished by at least 50 percent. Quite a reduction, huh? But hey, at least it still does its job! And besides, when weather conditions get really bad, one can always use the solar pump’s batteries.
No, not the everyday lithium ion batteries, but “water batteries.” These are simply storage tanks that are “charged up” or filled up with water so that in case the solar pump can’t be powered, water would still be readily available.
Walking on sunshine
The solar pump system has its beneficial effects on several levels: In economics, in agriculture, and in its manufacturing and maintenance costs.
Due to the improvements and innovations in manufacturing technology, the cost of photovoltaic cells or PVs (more commonly known as solar cells) has fallen dramatically by a whopping 90 percent since the 1970s. Plus, these PVs last from 20 to 25 years with life expectancies beyond 30 years.
Some manufacturers even opt to add mirror concentrators for extra sunlight plus more energy output at a lower production cost. This enables the invention to cast a wider net of consumers and market.
The impact of solar panels has generally been good, but some governments that subsidize solar pump systems have raised questions concerning the depths to which water can be drawn from, the time of day where maximum input is achieved, and proper storage of this collected water.
The positive side of the use of solar pumps, however, is quite admirable as seen in the application of drip irrigation for higher quantities of water collection and a better system for optimizing the water flow from the water supply to the irrigated crops. Because solar energy is clean, it takes away the issue of polluting groundwater; it is even practical in flat terrains and cuts down on the amount of waste produced.
Even if certain dams are closed, farmers are still able to water their crops because of this reservoir of water, thus eliminating the gruesome task of carrying liters and liters of water to and from the farmer’s crops. Here in the Philippines, the Pangasinan State University (PSU) has reported an increase in palay harvest with the use of solar pumps that water up to 1 ½ hectares of PSU planted palay.
In terms of its efficiency, just ten sunny hours of solar panels bathing under the sun can get you 900 gallons of water pumped! Moving the solar pumps around isn’t a problem since most of them are mobile. The key then to its efficiency and long-term economic benefits is the low labor and maintenance costs; it pretty much does it all for you.
Here comes the sun
There have been recent improvements in the solar pump and solar panel technology. Flexible solar panels are currently being manufactured, and a solar tracker has even been invented to facilitate their movement in accordance to the movement of the sun. This has increased energy gain by at least 40 percent.
Inventors have also utilized the use of a helical screw in order to ensure performance under low sunlight. With the addition of this helical screw to the positive displacement pumps, the solar pumps bring the water into a chamber and is forced out using the screw. Although this may slow the process, it only ensures consistent performance in longer distances and vertical rises.
Given all these advancements, one could say that the effectiveness of solar pumps and solar panels are on a skyward path; things are only getting better. Perhaps, if we even give this enough time and development, then the slow processing outside of sunlight peak hours and the limitations brought about by cold weather may be lessened and even eventually eliminated.
Alave, Kristine L. “Philippine Farmers among Least Mechanized in Southeast Asia.” Inquirer Global Nation. Philippine Daily Inquirer, 28 June 2012. Web. 31 Aug. 2013.
Borham, Ray. “Do Solar Panels Work When It’s Cloudy.” EzineArticles. SparkNET, 3 May 2010. Web. 31 Aug. 2013.
“Conergy Solar Water Pump Guide.” Kalale Solar Electrification Project. Stanford University, n.d. Web. 31 Aug. 2013. <http://www.stanford.edu/group/solarbenin/data/General%20Solar%20Water%20Pumping%20Info%20from%20Conergy/SolarWaterPumps-SF-US-0711-small.pdf>.
Polak, Paul, and Kendall Storaci. “SunWater: Affordable Solar Powered Pumps for Poor Farmers.” Indiegogo. Indiegogo, 6 May 2013. Web. 31 Aug. 2013.
“When to Choose a Solar Powered Water Pump.” Everything Ponds. Everything Ponds, n.d. Web. 31 Aug. 2013.
Sources for photos (in order)