In the South Caribbean, there is a place where the gentle waves wash upon the shore incessantly without tides. Much stronger than the waves of water on this beach are the waves of people that arrive in the morning and regress in the evening. The scene at La Playa Blanca, named for its wonderful white sand, is full of swimmers, jet skis, boats departing for scuba trips, and other boats blasting as if in the middle of a music video shoot.
La Playa Blanca lies on a peninsula in Colombia 25 miles away from the electric and vibrating city, Cartagena, a popular tourist destination and UNESCO world heritage site. The United Nations Educational, Scientific, and Cultural Organization has protected this city because it boasts the largest and most complete colonial military fortifications in all of South America. Starting in the late 1600s, Cartagena was a hotly contested focal point of the new world because it had the primary port of trade. This port brought the city wealth and diversity which the city still has today. All of this, including the areas’ fantastic year-round beaching weather, has motivated investors to set up cabanas along La Playa Blanca, but the only problem is there is no grid power there.
The narrow one-mile beach is undeniably beautiful. If you look carefully, you will sporadically see the solar panels that quietly provide power for the dozens of restaurants and hostels. There is no power company on the beach and no utility of any sort for that matter. This beach is proof of a community’s ability to thrive off-grid given solar technology and a little ingenuity.
Hostel after restaurant after hostel align to take up every inch of space down the beach, and yet each one is without grid power due to the beach’s isolation. Without electricity, the scenic location would not attract nearly so many travelers to the area, not to mention the people who live and work there. In addition to generators, simple solar systems provide the power needed to support the thousands of visitors flocking to the beach daily.
My hostel was aptly named Hostal Playa Blanca and was the farthest north on the beach. I was easily excited to learn more when I spotted the three solar panels gleaming on the rooftop. I questioned the staff with my infantile Spanish and unaccustomed ears. We started at the power strip behind the reception desk, from which you could take a running leap and land in the ocean. Here there is a five-plug power strip day and night. From 9 a.m. to 6 p.m. solar and batteries power only this single strip and a generator takes over from 6 p.m. to 6 a.m to power the entire hostel. There is no power during the three-hour gap in the morning. The old loud generator powers the same strip and the lights along with the fans in all the rooms. Following wires along the branch circuits like Sherlock Ohms ( yes Ohms 😊), I could see how easy it was to switch to the generator with a couple of manual switches.
The solar and battery source circuit is quite simple and is a very common design. The electricity produced by the solar panels flows into a storage room and then a charge controller. Charge controllers regulate the flow of electricity to batteries. In this case, two 150Ah lead acid batteries, connect to a small 1000W inverter changing the power from DC to AC. From the inverter, the AC circuit can be connected to one side of a manual switch to be flipped on or off at the user’s desire.
The best choice for the solar support structure is usually extruded aluminum and there is no exception in this case. Heavy amounts of humidity and salt bombard the beach and enact a corrosive war with metals. Aluminum is light and cheap and while it does oxidize, it does not rust; therefore, it serves as a perfect solar support structure.
The truth is that there is great potential for solar and batteries to replace generators at La Playa Blanca. Generators provide plenty of power but have many drawbacks. They are loud, use expensive diesel, and create harmful gases from their exhaust. Energy storage (i.e., batteries) are the key to success in modern off-grid systems. While the technology of lithium-ion technology in large storage applications is growing rapidly, cheaper lead-acid batteries can still easily get the job done.
Hostal Playa Blanca is a functioning example of an off-grid electrical system and given a little investment in more solar panels, a new inverter, and more batteries it could become a prime example of clean independence. For some time, solar and battery technology has been used to power many projects from small shacks to commercial buildings without the presence or need of a utility grid. It was wonderful to see a beautiful place in Colombia taking a step in the direction of power independence.
About the Author
Christian Williams graduated from the University of Colorado Boulder in 2015 with a degree in Mechanical Engineering and quickly found out how rewarding the solar industry was. He joined IPS as a PV System designer and drafter and has worked on projects ranging from custom off-grid to utility scale. His passions outside of work include connecting authentically, wood-working, mountain biking, climbing, and soccer. He flies around in a blue mini-van named Appa the Sky Bison so he can fit more people and activities in his life, but mostly its because it's rad stylish.