Powering an entire island with solar energy : Ta’u Micro grid

SolarCity Corporation is an American company which specializes in solar energy services. It’s merger with Elon Musk-led Tesla has demonstrated the world what such a union is capable of achieving within a short span of time — by running an entire island on solar energy.

Ta’u is a small island (44.31 km²) in American Samoa which until 2016 relied upon expensive diesel generators to suffice the electricity requirements of its small populace of 790 people. However, all this changed with Tesla and Solar City’s Ta’u grid project. The expensive and environmentally unfriendly diesel generators got replaced by SolarCity’s solar array and Tesla’s battery storage system/Tesla Powerpacks.

For the Ta’u microgrid project, a SolarCity panel array was created that’s made of more than 5300 panels with the capability of generating 1.4 megawatts of solar capacity. This was clubbed with a Tesla Powerpack commercial battery storage facility that has a capability of storing 6 megawatt hours of reserve capability in 60 Powerpacks. The resultant micro-grid could bring three full days worth of power for the island’s residents. Also the entire unit can recharge completely with only seven hours of straight sunlight exposure.

Island communities such as Ta’u where fuel has to be shipped at great costs from long distances have to face a lot of hardships and one of them being regular powercuts. Thanks to the installation of the micro-grid, they don’t have to worry about power outages or shortages any more. Besides bringing clean 24*7 energy to the consumers, the project also enables the island to save enormously on energy costs and also offset the use of over 108,500 gallons of diesel per year.

Installation of the panels wasn’t an easy task — Ta’u is nearly 4,000 miles from California. Extra efforts had to be made to withstand island’s extreme humidity and likelihood of severe tropical storms. As a result, the system was built with the capability of withstanding Category 5 hurricane winds. Nevertheless, the micro-grid project was put together from start to finish within a year.

Pros and Cons of the solar project

Pros-

→One of the main reasons for increased enthusiasm for solar energy generation around the world is because of the falling price of silicon over the past decade or so.

→The amount of solar energy generated is dependent on factors such as-

Ambient Temperature

Radiation

Technology Used

The first two factors are location dependent. Due to its location Ta’u receives ample sunlight throughout the year(except for a few stormy days). So we can safely say that the number of units produced are comparatively higher than in most of the North American regions.

Cons-

→Apparently , a “huge” amount of forest land had to be cleared to set up the plant. Going solar isn’t green if huge swatches of trees are going to be cut down. It may cause irreversible damage to the local flora and fauna. Especially islands have most fragile ecosystems.

→Adverse weather condition power generation capabilities can be an issue. Although the storage capacity for the project comes around 6MW- which would be sufficient for extreme cases such as those when sunlight is not available for prolonged days.