Solar Energy Drawbacks – Aug 2017

The EnerScope team is on location in Barbados.

One thing that strikes you when you when maneuvering through the island’s neighborhoods is that most houses have a large solar panel on the roof. You’d think it were a PV cell for generating electricity … its Solar thermal for hot water. Roughly 70% of the houses in Barbados have this installation which can be seen below. These installations offset more than 300 Gigawatts (300 000 megawatts) of energy each year. The only remaining question is why is it not used in 100% scenarios if it is cheap efficient and easy? Why is used only 70% of the time?

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Image showing solar installation on a house in Barbados

Truth be told, there several challenges with renewable energy.

Timing

Energy consumtpiton rised in the evening when lights are on, outdoor temperature fluctuates and there’s more people at home. The only problem is that NOT shine at night. Another problem is that electricty is hard to store. Can you save electricity to use tomorrow without having a battery? Even when it is stored, a large prtion is lost in the process. Tesla is doing a good job of this.

Costs

Research in solar technology is expensive and even though costs have been falling, upfront costs are still a barrier in this market. The semi-conductor material used in generating electricity from solar is expensive, hard to mine, has a large carbon emission footprint. Up to the late 2000s it was only 4% efficient. Efficiency has risen to roughly 20% now but still needs to come a long way.

Dependability

Cloud cover changes several times throughout the day in the tropics, and affects output and efficiency from both solar PV and solar thermal installations. For example if one needs 1000L of hot water at 80°C in 5 hours at an installation like a large house, water would need to be heated three times for roughly 2 hours each time. If sunshine is not as strong as it should be during the heating process then the water temperature suffers.

In conclusion, research has come a a long way in the past 10 years but needs to be super changed in the next 10. That requires funding and small businesses like EnerScope carrying research in the field.

 

Marcus