Geothermal

Due to Hawaii's volcanic activity, it has great potential for geothermal energy. But is it possible on Maui?

Geothermal energy plants drill into to sub-surface of the Earth, where water is stored within the rocks. Hot steam and fluids are released and brought up to generate electricity.

Current Geothermal Energy Production

Puna Geothermal Venture 38 MW

Location: Puna, Hawaii Island (Kilauea East Rift Zone)
Completed: 1993
Energy Cost: $0.16 kWh

There aren't currently any geothermal energy plants on Maui. There's only one proposed and completed plant on the Big Island. However, we can learn from the Puna Geothermal Venture to discover the feasibility of geothermal on Maui.

Benefits of Geothermal Energy

The primary benefits of geothermal are that it uses less space and produces a baseload capacity. How do those compare to our leading renewable energy sources: solar and wind?

Land Use

Acre: 43560 ft²

Geothermal 1-2 acres = 1MW
Geothermal energy requires by far the least amount of land per MW of any renewable source. This makes geothermal more appealing since less land would have to be purchased.

Solar 5-10 acres = 1MW
Solar farms can generate 1 MW for every 5-10 acres of land. In some cases, this land can be used for agriculture, with the shade of the solar panels even providing shade for animals.

Wind 60-80 acres = 1MW
Although each wind turbine only takes 1-2 acres, they need to be 60-80 acres apart to be most efficient. Like solar, most of this land could still be used for agriculture, depending on where it's built.

Visualization of acreage needed for renewables

Baseload Capacity

Baseload capacity: The generating equipment normally operated to serve loads on an around-the-clock basis.

While other renewables can only generate energy during certain conditions (i.e. daylight and wind), energy can be generated from geothermal at all times, producing a baseload capacity and giving it special importance among renewable energy sources. One of the few benefits of using oil for electricity is that it can always produce as much energy as is needed. If energy demands peak, more oil can be burned. Similarly, geothermal energy plants can increase production for a short period to fulfill increased demand, making it a near-perfect substitution for oil. Generating enough energy to support Maui at night could also massively cut costs on the expensive batteries that have to be built to retain solar energy. Because geothermal energy can be produced non-stop, consistently, it will be a valuable source of renewable energy on Maui if geothermal potential is found.

Geothermal Energy Potential on Maui

Map of Hawaiian Hot Spot

As proven above, geothermal is a competitive source of renewable energy when compared to solar and wind. Therefore, its biggest issue is availability. On the Big Island, geothermal hot spots are much easier to find due to its active volcanoes. The Puna Geothermal plant is located near the Kilauea rift which is easily located and the most consistently active part of a volcano.

On Maui, there is no longer an active volcano. However, there is a possibility that the island is still close enough to the Hawaiian Hot Spot that geothermal energy could be generated. At the moment this is only a theory, and the process of drilling to find geothermal potential is very costly. In conclusion, geothermal energy could help replace the baseload capacity generated by oil on Maui, but until geothermal potential can be surveyed more easily it is unlikely that Maui will use geothermal energy.