Green Energy Options in the Caribbean

The world is substantially increasing alternative energy sources, with little contribution to climate change, which is now recognized as a serious threat to the health of the planet. Earlier programs that aimed at “green” energy contributions of 10-20 percent are currently being studied for revision. As good as they are intended, they only offset the growth in carbon dioxide emission, which causes global warming.

If there is one place in this world where alternative energy should be a priority, it definitely is the Caribbean. Energy typically costs between $0.31-$0.38 per kWh (kiloWatt hour or “unit”), among the highest in the world. In the Caribbean, the trade winds and abundant sunshine provide ideal conditions for green energy.

While in many countries alternative energy needs subsidizing to be economically feasible, in the Caribbean it is already cheaper than burning diesel. Nevertheless, the use of green energy is far behind because of insufficient knowledge and lack of local financing.

In this article, I discuss the main sources of alternative energy in general, followed by specific options for the Caribbean as well as a summary of easy energy saving tips that have a significant impact in this region.

Wind Energy

Bigger windmills mean lower cost per kWh. Therefore the mainstream of the market is 2-3 MW (Mega Watt = 2000-3000 kW peak capacity) windmills. Their average yield is up to 1 MW, depending on wind conditions.

However, big systems also bring big problems with them: complexity of installation, accessibility and maintenance. But moreover, they require a very “strong” net (mains). Currently, even strong nets can not handle more than 25-30 percent participation of the big systems. The worst case scenario must be considered: maximum wind output at lowest power requirement at any time. In the western world, due to industrialization, the difference between minimum use and average use is not that big, but it reduces the wind penetration anyway.

As the average and maximum yield differ substantially, this further reduces the wind penetration. The big systems have (costly) options to waste energy into dummy loads in extreme cases, but practically, the maximum wind penetration is around 10 percent of the average power use. In Western hemispheres this is currently also seen as a practical limit because of the limitations to place windmills on land (people do not like the view). Ten percent, as useful as it is, is not even covering the growth of energy use.

In smaller markets—such as the Caribbean—big is not as beautiful as in the West as the nets are relatively small and the infrastructure to install and maintain the big systems is limited. A company from the Netherlands recognized this gap and delivers solutions in the form of mid-range windmills (80-250 kW) and developed intelligent control systems that dynamically balance energy output and requirement. This can significantly increase the wind penetration to 60 percent or more. The smaller systems are easy to install and maintain, and for markets like the Caribbean this is clearly the way to go.

Solar

Photovoltaic systems used to be only suitable for small-scale energy requirements. This is changing thanks to increasing production and subsidized use by western governments. Currently PV solar can not compete with wind energy, but on the long term drastic improvements are to be expected. A long term vision that new houses are covered with solar roofs is getting within sight.

Solar systems have the advantage of low maintenance (only cleaning) and can also save some cost by replacing traditional roofing systems.

In the Caribbean, PV solar systems are already getting close to the cost of generating electricity from fossil sources because of the intense sunshine and high cost of diesel, Once the production cost of PV solar systems further decreases, they will create savings for their owners. This will likely induce a massive breakthrough.

An even more rewarding source of solar energy in the Caribbean are solar water heaters. They produce abundant hot water and the installed cost can be as low as $800 for a 50 gallon system. In many cases they pay for themselves in two to three years, yet they are far from popular.

An aspect specific to solar systems in the Caribbean is protection against hurricanes. In affected areas, proper measures need to be taken. PV systems should best be covered with plywood panels, ready to fit. Solar water heaters should either be covered or taken out in case of a hurricane. While all this requires attention in designing the setup, the good news is that the related cost is not significant.

Hydro

Using water force as an energy source is not new. Some countries, such as Canada, rely heavily on hydro power. Clearly, the availability is limited to specific areas. And to make efficient use of hydro power, the scale must be sufficient. While the contribution of hydro is important, it is not expected to belong to the mainstream in terms of aggressive growth of green energy on a global basis. In the Caribbean, there are options but cost may be a prohibitive factor.