
The revolution in renewables and energy storage, has, however, been making things easier. It is now common for us to specify and install solar and energy storage systems in these areas. What has interested me about this in particular is that crunching the numbers suggests what has traditionally been a problem for these places could become an advantage.
Typically hybrid solutions would involve solar, wind or another intermittent renewable electricity source, fossil-fuelled power generation and energy storage, being used as a buffer, but increasingly it is clear there is simply no need for the fossil-fuelled generation.
Because of the climate and energy demand patterns, the Tropics, with some exceptions (particularly to the right on the equator), offer the opportunity to do away with the generator/power station entirely. The reasons for this lie around the amount of solar irradiation, the constancy of daylight/night and the constancy of demand. Solar generation is much more effective than in the UK, for example, offering 50-100% more output per unit deployed. However, more important is that in the tropics you get around 12 hours of sunlight and 12 hours of dark every day and you have broadly the same pattern of energy loads throughout the year. This makes sizing of solar and battery systems simple because you don’t have to make an oversized system for a short term peak and you don’t have a season with low output. (There are some areas very near the equator that aren’t so ideal because of cloud and rainfall, such as Singapore - caused by Hadley cells from geographical memory.)
The result of this means that with the decline in price and increase in efficiency of solar and energy storage, it is now already the case that on a new development they should be the standard solution. There is no reason that existing developments cannot be retrofitted with solar energy or connect into an increasingly solar electrical system and at ever reducing cost.
With the electrification of our transport system this leads naturally to a point where islands/places will be entirely independent in terms of energy. They can be genuinely zero carbon (not just “net”) and all-electric; it is difficult to overstate how good this will be.
Discussing this thought, some people have raised the issue of extreme weather events and whether this would be more or less resilient than the standard solution. I think the answer is it will depend, but the system could certainly be designed to offer greater resilience by distributing generation and storage more. We have seen this kind of thing in Puerto Rico with Tesla.
Unfortunately this won’t apply in the UK because our energy demand increases in the winter when our solar generation falls and our daily energy demand typically peaks at about 4-7pm just as solar supply is declining or absent.
So it is a rosy future for much of the tropics but we can still benefit here. Peak electrical demand in London is actually during the summer but it is important to remember that this may change as we electrify buildings and transport. As buildings become more thermally efficient, solar and energy storage could begin to move from a minor element in our energy system to one of two or three energy sources: perhaps wind, nuclear and solar with some flexible gas back-up and energy storage.
This blog was written by Barny Evans, Technical Director, Sustainable Places, Energy and Waste