by Ku‘ulei Funn, Science & Environment
In January, Hawai‘i Governor Linda
Lingle announced a strategic energy plan that supports development
of alternative energy sources that would ultimately allow the
islands to use their own resources to become energy independent.
The plan will help the state to reduce, eventually, its dependence
on crude oil, saving us all money in the long run. Lingle believes
that one consequence of her plan, should it be successful,
would be the establishment of Hawai‘i as a global leader
in the development of renewable energy sources.
Hawai‘i has five sources of renewable energy that can be
readily developed: wind, solar, tidal, geothermal, and biomass.
It is sunny year round with nearly year-around trade winds. Located
in the middle of the ocean with hundreds of miles of coastline,
the islands can generate energy from waves, tides, and thermal
conversion layers. It sits on top of a geothermal heat sink generated
by our volcanic origins and active volcanoes. Its growing season
is year around, and it already has a history of converting sugar
cane and garbage biomass to electricity.
Today’s solar technology uses heat from the sun to generate
electricity. Solar energy can be obtained directly or indirectly.
Passive eolar energy uses the sun’s heat directly to heat
buildings by convection and indirectly by heating water. Passive
solar can also be used with photovoltaic technology in which
light-sensitive panels convert energy from the sun to electricity.
An entire building at Pearl Harbor has been roofed with photovoltaic
cells that provide all its energy needs.
Active solar uses mirrors to concentrate solar energy to create
large amounts of electricity. At present Hawai‘i has no
active solar projects, but those that have been created in the
southwestern United States and in France have been remarkably
Wind energy is produced when a turbine transforms kinetic energy
into electrical energy. One wind turbine can power up to 500
homes. The Kaheawa Wind Farm on the island of Maui consists of
20 wind turbines and provides 9 percent the island’s power.
It is the largest wind power production in the state of Hawai‘i.
Ocean energy has the greatest potential in our state. With ocean-based
technologies such as wave energy, tide energy, and thermal energy,
there are great possibilities for our state. The Ocean Thermal
Energy Conversion Plant on the Big Island uses the temperature
differences in the ocean to generate electricity. Cold water
can be used to air condition buildings, and farm cold water life
such as shell fish and kelp.
Hawai‘i may be unique in its potential to develop geothermal
energy. Other areas have volcanoes, but Hawai‘i’s
reservoirs of cooling magma are close to highly developed areas
that already have established infrastructure. The Puna Geothermal
Venture located on the Big Island of Hawai‘i supplies about
25 percent of the islands electricity to over 162,000 residents.
With the threat of global warming rising, it is necessary that
we look into ways to power our earth without damaging what is
left. Governor Lingle was brave in her attempt to establish such
ideas, and we would be foolish not to meet her challenge.
Renewable energy--A matter of survival
Although it may sound like a new idea, renewable energy is
an idea that has been around for a long time. As early as 1.5
million years ago, human-like primates were using passive solar
energy to heat rocks they could carry into caves to warm themseves
overnight. By 400,000 B.C.E., homo erectus was using fire generated
from biomass--dead wood and animal dung.
Concentrated solar energy was used as early as 212 B.C.E. when
Greek mathematician Archimedes used large mirrors to fire Persian
warships during a battle. This was one of the first recorded
uses of any type of renewable energy; however, for most of
human history, people have regularly used natural energy sources
to fuel their activities of daily life.
From their first recorded uses in China, Afghanistan, and Persia,
around 50 C.E., wind and watermills have been used across Asia
and Europe to grind wheat and corn and crush minerals. They
were still being used in Renaissance Spain, when Miguel de
Cervantes described his hero, Don Quixote, attacking one.
In 1838 a French experimental physicist named Edmund Becquerel
discovered that electricity could be generated using the light
of the sun on an electrolytic cell. This was the beginning
of today’s photovoltaic technology; it took so long to
get to today’s level because the industrial revolution
found fossil fuel—coal, oil, and natural gas—abundant,
therefore cheap, and relatively easy to use.
Unfortunately, 200 years of reliance on fossil fuels has released
so much carbon dioxide into the earth’s atmosphere that
the earth’s climate is changing. Carbon dioxide traps
the sun’s infrared radiation in the atmosphere, which
causes it to retain heat, which in turns warms up the whole
In 1896, Swedish chemist Svante Arrhenius calculated that the
surface of the earth was about 30º C warmer with an atmosphere
than it would be without one. He concluded then that the global-warming
effect would be beneficial to the planet because it would stimulate
plant growth and foster a larger population.
Carbon dioxide levels have risen about 25 percent since Arrhenius
made his prediction. Over the past 110 years this increase
in CO2 has caused a 0.5º C increase in global temperature.
Earth’s atmosphere and climate are complex interrelated
systems, and most scientists today believe this warming trend
has reached a tipping point where, if we continue burning fossil
fuels at our present rate the system will shift. Tropical temperatures
will move into north and south temperate zones, melting arctic
tundra and icecaps, causing dramatic changes to ocean currents
and climate patterns and catastrophic changes to the biosphere.
Although we cannot easily reverse the damage that has been
done, we can move to prevent further global warming by using
alternate energy sources.