Introduction
As of this writing (December 2021), we are just beginning to explore two solar projects: solar food dryer and micro-solar electric systems for isolated homes. We do not yet know if these projects will be successful or sustainable. However, the reality is that we must keep trying new interventions if we hope to improve the life of the average Jan Jose resident.
Solar Food Dryer
Most of us living in wealthier countries are used to getting produce year round, even if the produce is not in season. The poor of the world do not have that luxury. As an example, mangoes in San Jose are only available for a couple months a year. Once the mango season is over people must wait another 9-10 months before they can enjoy mangoes again. Drying fruits and vegetables when in season is one way to preserve the foods for later consumption. A solar food dryer can be built in San Jose for a relatively small amount of money. The day to day operation after that is free because there are no energy costs. The sun provides the energy. We have built a simple solar food dryer and have started experimenting with various fruits and vegetables to see what works well. Once we have some proficiency with the dryer will will help interested San Jose residents build and operate their own solar food dryer. The hope is to expand the variety of foods available year round. This can improve nutrition, as well as variety in their diet.
Solar PV Electricity
About 12 years ago the electric grid came to parts of San Jose. Only a very limited number of homes that live near the main road could access that electricity. Then comes the harder part of paying the monthly electric bill. Poorer families and families far removed from the power lines must live without electricity. This means from about 7 pm to 5 am they are in the dark. Meals are cooked in the dark and homework for school children must be done by candle light. Given the ubiquity of cell phones, most isolated homes have no easy way to charge their $30 cell phones. They must often walk more than an hour to charge their phones at a home that has grid electricity. We are starting a pilot project to introduce a very basic solar electric system into interested isolated homes. Another group installed solar electric systems into a limited number of homes about 5 years ago. This group left and has not returned. Many people were not included in that earlier project but still hope to get lights and the ability to charge cell phones in their home.
Our pilot project involves installing a 100 watt solar panel, one battery, four LED lights, and the ability to charge anything that can use a USB plug. We estimate the cost per home to be about $500. The home owner will need to pay about $40 of that. We have six families interested in this pilot phase of the project as of January 2022. The hardest part of most solar systems is that the battery must be replaced in 2-6 years and is by far the costliest part of the system. We are hopeful that recipients of our system will work together to pay about $5/month so that when their battery dies they will have saved up enough to purchase a replacement battery.
In February 2022 we had enough solar equipment delivered to install 10 simple solar systems. During our May 2022 brigade to San Jose, we installed three solar systems. Although it took significant time to mobilize the interested people because of the distances involved and communication difficulties, the three installs were successful. We held 3 more classes for people interested in solar systems and have 40 families signed up to receive the simple solar systems. To keep things as simple and low cost as possible we have to date mounted the solar panels on the roofs of the house. We had a carpenter build very simple battery boxes that also hold the charge controller. For this initial phase of the project we are not including inverters until the homeowner feels comfortable managing the battery. Once people understand our reasoning they are more accepting of not having “house” plugs initially.
While in San Jose in May we evaluated a couple non-functioning solar systems that were installed by another group a few years ago. These systems are much more polished than our systems with a fully enclosed custom made steel box that includes a charge controller and inverter. All these systems also pole mount the PV panels. One system had a non-functioning inverter. Unfortunately, because of the custom construction of the controller box, a simple swap out of the damaged inverter did not seem possible. Another system we evaluated had a dead battery. The home owner had bought a new battery to replace the old battery but the new battery only lasted a few weeks. He does not have enough money to buy a third battery and shops that sell batteries will not warranty a battery. A third system we came across had an exposed and broken conduit for the wires coming from the pole-mounted PV panel to the controller. It is only a matter of time before this system stops working. Hopefully that homeowner took our suggestion and covered the exposed wires. Given we plan to continue working in the San Jose area we hope we can solve similar problems that might arise in the systems we installed.