Geothermal Energy

Potential

Hawaii Energy Policy Forum

HCEI Briefing & Policy Dialogue

March 30, 2011

Potential significant contribution to clean energy future

• Hawaii Island

Already important

– 13-18% of electricity distributed by HELCO is geothermal

Additional large untapped potential

• Maui

Untapped potential

• Statewide

Could be significant

If islands’ grids were connected

2

Diesel

Fuel oil

Naptha

Hydro

Wind

Geothermal

Solar

Geothermal 17%

HELCO electricity distributed in 2010

Resource data have not been updated

3

• Research from 30+ years ago

U.H., USGS & other researchers

Not comprehensive in all areas with

potential

• Exploration technologies have

advanced

• Summarized in “Assessment of

Energy Reserves & Costs of

Geothermal Resources In Hawaii”

2005 report to DBEDT by

GeothermEx, Inc.

HCEI assumes increased geothermal generation

• Assumes conservative 102 MW

To be used on island where it’s produced

Big Island: 60 MW (currently permitted)

Maui: 42 MW assumed (30% of its mean capacity)

• Meeting HCEI goals will assure that greenhouse gas goals are also met

Geothermal emits essentially 0 greenhouse gases

Displaces CO2 from fossil fuel power plants

• Presently, geothermal is reduced at night

30 MW capacity not fully used

Possible solution: load shifting; increase off peak demand

4

HELCO’s generation portfolio

5

Estimated Geothermal Reserves in Hawaii

Rift Zone Minimum Capacity (MW) Mean Capacity (MW)

Lower Kilauea E Rift 181 438

Upper Kilauea E Rift 110 339

Lower Kilauea SW Rift 64 193

Upper Kilauea SW Rift 68 201

Mauna Loa SW Rift 35 125

Mauna Loa NE Rift 22 75

Hualalai 7 25

Hawaii Island subtotal 488 1396

Haleakala SW Rift 20 69

Haleakala E Rift 18 70

Maui subtotal 38 139

Other islands -- --

State total 526 1535

Source: GeothermEx 20056

Does not mean a

reservoir can be

economically or

responsibly

developed!

“Reserves” =

recoverable heat

anticipated to be

present at drillable

depths.

7

8

Estimated costs of new geothermal electricity

• Calculated to be appx. $0.08 / kWh from a new 30-MW plant (in 2005)

Assumptions

– Capital costs $2500-$5000 / installed kW

– O&M costs $0.04-$0.06 / kWh

– Initial drilling costs $4 million - $9 million / well

Source: GeothermEx, 2005

• How would new geothermal be financed?

Possible role for public funds in resource assessment

– E.g., ARRA is supporting Maui exploration

Drilling, power plant development: private investment

PPA needed with utility

9

Challenges to geothermal expansion

10

• Market

Presently limited to single island grid

– Interisland cable?

Presently limited by lack of off-peak demand

– Develop alternative markets?

o Liquid fuel: ammonia, hydrogen

o Direct use of heat

o Electric vehicles

Competitive bid needed (utility RFP)

– If > 3 MW on Maui, Hawaii

• Knowledge of resource

Exploration outside of KERZ minimal

More challenges to geothermal expansion

• Regulatory / permitting issues

New / expanded subzones?

County geothermal resource permits

Conservation district use permits

Environmental studies

Mining leases, surface leases

Clean air permits

Well / injection well permits

• Public acceptance

Health, environment, culture

Controversial in past

11

Other work of interest: Downhole Heat Exchanger test

12

• At Malama Ki well,

Puna

• Q: Can useful heat

be extracted for ag &

similar purposes from

the warm subsurface

water?

• A: Flow is fairly high,

but warm water layer is

too thin

Work done by Oregon Institute of Technology, 2007

Other work of interest: Direct (non-electric) Use

• Community Geothermal Technology Program, 1987-89

Small grants to entrepreneurs through DBEDT / HNEI / USDOE

Demonstrations used geothermal steam or heat, including:

– Fruit drying

– Lumber drying

– Cloth dyeing

– Greenhouse heating

• Feasibility Study of Geothermal Direct Use, 2007

County of Hawaii R&D contract, USDOE funding

Potentially viable enterprises

– Greenhouses

– Pasteurization of potting media

– Biodiesel production

– Lumber kilns

13

Geothermal is an important part of renewable portfolio

• Geothermal energy is significant now on Big Island

• Cost is competitive

Less than imported oil

Less than many other renewables

• Additional geothermal can be developed

Reserves on Hawaii, Maui

However, exactly how much & where is unknown

• Alternative markets could play a role

Liquid fuel

Electric vehicles

Direct use of heat

14

15

Mahalo

Andrea T. Gill

Renewable Energy Specialist

State Energy Office

agill@dbedt.hawaii.gov

16

17