In depth
Solar power in Cuba: sunshine, an ageing grid and what the rules allow
Cuba receives some of the strongest sunlight in the Caribbean, and it depends on an electricity grid that has struggled to keep up with demand. That combination explains the growing interest in solar energy. This guide explains how much sun the island gets, how its power system works, what role solar and other renewables play, what the legal and import rules allow, and what questions anyone assessing a solar project in Cuba should ask.
How much sun
Solar resource is measured as global horizontal irradiation, the energy from the sun falling on a flat surface, usually expressed in kilowatt-hours per square metre per day. Across most of Cuba the average is around five kilowatt-hours per square metre per day, with the highest values in the south-east and the lowest in the north-west in winter. Compared with northern Europe, where the figure may be between two and three, Cuba has roughly double the resource, and a given panel will produce much more electricity over a year.
The World Bank's Global Solar Atlas publishes maps and downloadable data for any location, and is the standard first stop for anyone studying a site. The values are modelled from satellite data, so a detailed project should rely on measurements and on a design that considers shading, orientation, temperature and soiling.
The electricity system today
Cuba's electricity is generated mostly in thermal power stations that burn fuel oil and crude oil, supplemented by smaller diesel and gas-fired units, some sugar-industry biomass plants and a small share of hydro, wind and solar. The older thermal plants, many built decades ago with Soviet technology, are subject to breakdowns, and they depend on fuel that must be imported or produced domestically from heavy crude.
As a result, outages have become frequent in recent years, with scheduled blackouts in many provinces and a number of nationwide grid failures reported in 2024. The government has announced plans to repair and replace thermal units, to add distributed generation, and to build solar parks to reduce dependence on fuel. Updates are published by the electricity company and the energy ministry.
Renewables policy
Cuba's national policy sets a goal of raising the share of renewable energy in electricity generation substantially by 2030, with targets that have been stated in several official documents. The legal basis includes a decree-law adopted in 2019 on the development of renewable energy sources and its regulations. The measures include incentives for equipment, rules for connection to the grid and provisions for private and state producers.
In practice, the pace of construction has been affected by finance, by the need to import equipment and by sanctions that complicate payments and shipping. Announcements describe solar parks of around twenty megawatts built with support from partner countries, and the government has said that more are planned. A reader should distinguish between a planned capacity, a capacity under construction and a capacity connected and producing.
Wind, hydro and bioenergy
Solar is not the only renewable resource. Wind parks operate at sites such as Gibara in Holguín province, which have a modest capacity. Small hydroelectric plants use the rivers in the mountains of the east and centre. Bagasse, the fibrous residue of sugar cane, has long been burned in sugar mills to produce steam and electricity, and some mills sell power to the grid. Biogas from livestock and waste is used on a small scale.
Each source has constraints. Wind is moderate and varies with the season. Hydro is limited by the small size of Cuban rivers and by drought. Bagasse depends on the sugar harvest, which has fallen sharply over the decades. Solar, with its large resource and modular nature, therefore attracts most attention.
Households, businesses and imports
Households and small businesses have also turned to solar systems to cope with blackouts. Rooftop panels with batteries and inverters supply lights, refrigerators and other essentials. In recent years the government has eased the rules on imports of solar equipment, including reduced or eliminated tariffs for certain components, and has allowed small private businesses to import and sell equipment. The details change and are announced through resolutions in the Gaceta Oficial.
Anyone considering an installation should check the rules on connection to the grid, on inverter approvals, on the permitted capacity for private systems and on safety standards. Battery systems add cost but provide independence from outages, and the choice between grid-tied and off-grid designs depends on the reliability of the local grid.
Questions to ask about any project
A prospective investor, supplier or customer should ask a few simple questions. Who owns the site and the output? What is the contract for selling power and in what currency is payment made? How is equipment imported, and who pays duties? What are the warranties and who provides maintenance? How are batteries and panels handled at the end of their life? And what do US and other sanctions rules allow for the parties involved? The answers should be in writing and refer to published rules.
This page is educational. It does not sell, install or finance solar systems and does not represent any company.
Sizing a home system: loads, panels and batteries
A home solar system is sized from the bottom up. Begin by listing the appliances you want to run, their power in watts and the hours per day they operate, then add up the daily energy in watt-hours. A refrigerator, a few lights, a fan, a television and phone chargers may total a few kilowatt-hours a day. The solar array must produce at least that amount on an average day, allowing for losses of about twenty to thirty per cent in cables, inverter and dust.
With around five peak sun hours per day, a daily need of five kilowatt-hours calls for roughly one and a half kilowatts of panels. Batteries then store energy for the night and for outages. Their usable capacity is smaller than the label suggests, since most chemistries should not be fully discharged. Lithium iron phosphate batteries allow deeper discharge and longer life than lead-acid, at higher initial cost. The inverter converts direct current to alternating current and must be rated for the largest load, including the surge when a refrigerator compressor starts.
Solar water heating
Where the aim is hot water, a solar thermal collector is usually more efficient than using electricity from panels. A flat-plate or evacuated-tube collector heats water directly, and a tank stores it. Cuba has promoted solar water heaters in hotels, hospitals and homes as a way to reduce electricity and fuel use. A properly sized system can supply most of the hot water needed by a household in the tropics, with a backup for rainy days.
Hurricanes, salt and maintenance
Equipment in Cuba faces demanding conditions. Panels must be fixed to resist high winds, with mounting structures anchored into the roof structure or a concrete base, and cables must be secured. Near the coast, salt in the air accelerates corrosion, so stainless steel or well-coated fasteners and marine-grade connections are important. Dust and bird droppings reduce output and need periodic cleaning with water and a soft brush, preferably in the cooler part of the day.
Before a hurricane, some owners disconnect and store batteries and inverters, and lower or protect panels if they can be removed. After a storm, inspect mountings, cables and the roof for damage before reconnecting. Batteries should be kept cool and ventilated, because heat shortens their life and some chemistries can be hazardous if damaged.
Safety and standards
Electrical safety is critical. Wiring must be the right size for the current, protected by fuses or breakers, and properly earthed. Direct-current circuits from panels and batteries can carry high energy and arcs are dangerous, so installers use equipment designed for them. The International Electrotechnical Commission publishes standards for photovoltaic systems that many manufacturers follow. In Cuba, national rules and the electricity company set conditions for connecting to the grid, and anyone planning a system should confirm them first.
Questions about cost and payback
Anyone considering solar should compare costs with value. The upfront cost of panels, inverter, batteries and installation is the main expense. The value comes from the electricity produced, from avoided fuel for generators and from the benefit of keeping lights and refrigeration on during outages. In places where the grid is unreliable, the value of backup power can exceed the value of the energy itself. A simple payback calculation should include the replacement of batteries, which typically wear out sooner than panels, and the cost of maintenance.
Community solar and shared energy ideas
Communities in several countries share solar resources through community arrays, cooperatives and microgrids. In such systems, a group of households or businesses invests in a shared installation and divides the energy or its savings. In Cuba, small community projects could help neighbourhoods keep essential services running during outages, such as water pumps, clinics and schools. Their success depends on rules, finance, equipment and organisation. Studying examples elsewhere gives ideas for what might work.
Common questions
- How sunny is Cuba?
- Most of the island receives about five kilowatt-hours per square metre per day of solar energy, roughly double northern Europe.
- Why are there blackouts?
- Mainly because of ageing thermal plants, fuel shortages and a strained grid. The energy ministry and the electricity company publish updates.
- Is private solar allowed?
- Yes, under rules set by Cuban authorities that have been eased in recent years. Check the current resolutions.
- Where can I find solar data?
- The Global Solar Atlas gives free maps and data for any location.
- Do you sell solar systems?
- No. This page is information only.
- How long do solar panels last?
- Typically 25 years or more, with gradual loss of output. Inverters last about ten to fifteen years, and batteries from five to fifteen years depending on type and use.
- Can panels withstand a hurricane?
- Properly installed and anchored panels can withstand strong winds, but extreme storms can damage them. Mounting design and maintenance matter.
- Is solar water heating cheaper than electric heating?
- Over time, usually yes, especially where electricity is costly or unreliable. Initial costs are recovered through savings.
- Can I run an air conditioner on solar?
- It is possible with a sufficiently large array, inverter and batteries, but air conditioning uses much energy and increases the cost of the system. Many users start with lights, fans, refrigeration and electronics, and add more later.
Official sources and where to go next
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