Why solar and batteries?
Solar power is renewable and avoids reliance on expensive, scarce fuels in Cuba.
Batteries are silent and safe, avoiding the dangers of CO poisoning or fire from generators.
A 2–3 kWh system can reliably power refrigeration through blackouts of up to a day and, when paired with 600–1000 W of solar, can provide continuous service.
Such systems also enable electric cooking, reducing dependence on propane or charcoal, and provide lighting and ventilation.
Larger systems would be required for all-night air conditioning.)
On a broader scale, displacing gas and diesel generators significantly reduces pollution.
Here is a simple overview of what you need to know about batteries and solar
1. Capacity - The amount of energy that can be stored in the battery.
How big the battery needs to be to accomodate all the needs for the time there is no power, often measured in Wh or kWh (1kWh is just 1000Wh)
If a refrigerator typically uses about 1.3kWh (1300Wh) per day and a fan uses about the same, you would need 2600Wh of capacity to last a day
2. Power - How quickly energy is used
How fast energy is used, often measured in W or kW
This measures how quickly you go through your capacity, but also batteries are limited to how quickly they can provide energy
If your same fridge uses 300W (when running) and your hot plate is using 1500W (on Max) then your battery need to be able to provide 1800W in the wost case
A battery must handle both:
1. Enough capacity to last the day (or however long the power is out)
2. Enough power output to run devices at the same time.
3. Solar Panels - Recharging your battery when the power is out
This determines how quickly your batteries recharge when the sun is out, measured in W
The sun shines about 5h a day in Cuba, so a 100W panel will generate 500Wh in a day. A 200W panel... twice that
4. Shipping Equipment - Getting the equipment to its destination
Batteries cannot go on a passenger aircraft. They can go by ship or cargo air freight.
Solar panels are bulky but you can take them in checked baggage
5. Batteries and Sizing - What battery is going to serve your needs
Capacity and Power are the biggest factors, but there are others
You have to make sure the solar panels match your battery
6. Specifications - Understanding all the numbers on the batteries and solar panels and how to wire them up so nothing blows up
7. There is a whole estimator spreadsheet where you enter what appliances the familiy in Cuba wants to back up and it estimates the size, price and weight of what you need.
For more information, suggestions for improvements or question contact the LightUp Project