Geothermal Electric Limited geologists have conducted technical assessments of all hot springs in Fiji.
More often, hot water flows to the surface and bubbles of steam appear if the
water is above boiling point – just like a vigorously boiling kettle. This is the case in Fiji. These hot springs have been
used for cooking since ancient times.
Although hot springs can give a hint about where to look, finding heated water at the right temperature
and quantity to power a geothermal electricity plant can be very difficult. Drilling to explore for water usually involves
holes between 300 to 3,000 metres deep, or even further -- compared with 30 metres for a typical village well. Often
drill-holes have to be abandoned because they remain dry, even though it may be discovered later that water is not far away.
That's why, although decisions on where to drill make use of geological science as much as possible, there is a high element of
luck when drilling for geothermal hot water. At up to $5 million per drill hole, it is expensive for the exploration company if
luck runs out.
The conclusion: Fiji is very lucky to be on the "Ring of fire". Hopefully, good luck will combine with
science to make the geothermal drilling program succeed.
Click for a diagram of
how heat in a geothermal reservoir under the earth’s surface is accessed by drilling.