Research Final Draft: Alaska is the Energy Frontier

Research Draft:  Alaska is the Energy Frontier

David Apperson

The current use of unsustainable resources to supply a growing energy demand will lead to an energy collapse unless better methods are developed to power our world.  According to Energy and the Environment by Robert Ristinen, in 2005 86% of the energy used in the U.S. came from nonrenewable resources including petroleum, coal, and natural gas (Ristinen, & Kraushaar, 2006)).  Energy must come from sources other than fossil fuels if humans are to survive but the only way demand can be met is if local communities utilize the strongest sources of clean energy in their area.  Renewable sources must become the backbone of our energy economy, not the decoration.  The only way to achieve this is to build large scale industrial facilities that can replace existing coal and gas turbine power plants.  Although renewable energy is often viewed on a small scale, systems in Alaska illustrate that the best use of sustainable resources is to redistribute load onto regional scale renewable sources because it will reduce the impact of existing fossil fuel sources, give communities energy independence and create a more stable energy system.

Humans are destroying the world.  One of the biggest ways we do this is by how we produce electricity.  Unfortunately for us and the Earth, the biggest and most abundant source for energy, the sun, remains relatively untapped compared to coal, oil and natural gas reserves.  The reason why this is still the case is because existing infrastructure is built around these fossil fuel technologies and the industries providing power via these sources have considerable inertia.  A major transformation must occur to slow the rate of climate change (Moselle, Padilla, & Schmalensee, 2010).  Fortunately the winds of change are blowing as America is starting to realize the size of the grave that is being dug.  Unfortunately, it will require a massive reinvestment into new infrastructure and renewable technologies, without energy subsidies, must be economically competitive with conventional fossil fuel sources if any momentum is to be gained (Skoglund, Leijon, Rehn, Lindahl, Waters, 2010).  The natural world is a chaotic display of energy flowing in raw forms that is only waiting to be harnessed; the problem to be solved is one of engineering.

Alaska is the energy frontier for America and has a fantastic opportunity to lead the charge towards an electric economy because of its many sustainable energy sources.  Adding to its uniqueness, Alaska has over 200 villages that are isolated from the main Railbelt power grid that supplies the larger municipalities (Drouilhet & Shirazi, 2002).  Because each of these communities still requires electricity to provide light and power, renewable sources are a prime selection to offset the high cost of diesel fuel, allowing Alaska to become a perfect proving ground for new technologies (Painuly, 2000).  “In addition, the high operations and maintenance (O&M) costs of diesel-generating stations contribute to electric  generation costs that average nearly $0.40/kWh and can be as high as $1.00/kWh” (Cotrell & Pratt, 2003). Although Alaska’s high latitude makes it less suitable for large solar plants, because of its large size it is privileged to have more coastline than the rest of the United States combined (Benson, 1998).  Where the land meets the sea, there is wind, where there is wind there is energy potential waiting to be tapped.  Traced back far enough, all wind is generated by the sun unequally heating the Earth, so wind energy is still tapping free solar energy, just less directly.  On top of fantastic wind resources, Alaska’s size and latitude again give the benefit of large glaciers and ice fields which provide long term supplies for hydroelectric projects.

Wind:  Nineteen Alaskan cities or villages have one or more grid tied utility scale wind turbines that supply a substantial portion of its energy needs.  A short list includes:  Shaktoolik, Kotzebue, Wales, St. Paul, Port Heiden, Selawik, Toksook Bay, Kasigluk and Kodiak (Fay, Keith, & Schworer, 2010).  The largest and least expensive system in terms of kilo-watts produced for every dollar invested is Kodiak’s Pillar Mountain project at $4800 per kW, the total project cost was $21.4 million (Fay, Keith, & Schworer, 2010).  The larger the project, the lower the cost per kilo-watt produced.  Any new project requires considerable startup investment regardless of size, so a few big systems are more valuable than many small ones.  The reason why all these communities are opting for expensive wind turbines is because diesel fuel is even more expensive.  For small communities that exist far from the main grid, the standby technology to produce electricity is diesel.  Large generators run continuously to provide these small outcroppings of civilization with usable power, and are also costing them massive amounts of money.  In the village of Toksook Bay three 100 kilo-Watt (kW) wind turbines will keep 52,000 gallons of fuel a year from being burned, saving approximately $200,000 a year depending on fuel prices (Fay, Keith, & Schworer, 2010).  These systems pay for themselves quickly.  Unfortunately the downside is that the wind does not always blow at the exact speed to maximally produce AC electricity at 120 volts and 60 Hz.  This problem is termed “penetration”, describing the ability of a wind system to offset the amount of diesel being burned.  To overcome this hurdle, considerable research is being done to store excess wind energy to keep penetration high even while the wind is not blowing fast enough.  One way this is achieved is by storing the surplus energy in large batteries.  “The high cost of operation of the diesel means that substantial savings can be realized by using battery storage to meet the  system performance requirements without  the diesel” (Miller, Zrebiec, Delmerico, Hunt and Achenbach, 1996).

The Alaska Center for Energy and Power (ACEP) and the National Renewable Energy Laboratory (NREL) are currently conducting research in this field.  NREL has been actively working on integrating wind and diesel in Alaska for over ten years. The village of Wales currently enjoys reduced energy costs from two 65 kW Atlantic Orient Corporation wind turbines installed in 2000, NREL had been designing and troubleshooting the system since 1995 (Drouilhet & Shirazi, 2002).  The integrated wind diesel system in Wales is quite robust and demonstrates a versatile and well designed system.  The original two turbines were built to offset the cost of three diesel generators and charge a 240 VDC battery pack composed of 200 individual 1.2 VDC cells (Drouilhet & Shirazi, 2002).  The system as a whole is capable of operating across 5 different modes depending on which components of the system are fully operational.  In the highest mode, all components are functioning normally but if a problem were to occur with one component (perhaps wind speed is too low, or the AC to DC rotary converter malfunctions and breaks) then the system automatically drops down to a lower mode which does not involve that component.  “The most critical task of the wind-diesel hybrid power system is to maintain constant voltage and frequency in all modes of operation” (Drouilhet & Shirazi, 2002).  Redundancy and resiliency in designs will be critical to successful operation of any renewable system in the harsh environments found in Alaska.  Another problem that plagues wind power comes when a power outage occurs when the main source of electricity goes down.  During a power outage, although the main source is down, the turbine is still operating and pumping electricity into the grid, leaving the power lines charged.  If the power from the wind turbine is not switched off immediately when the grid loses main power, it is possible for line men to enter a dangerous environment if they are working on or near energized lines that they think are dead.  This problem is successfully avoided with advanced switchgear that cuts power from the wind turbine once main power is lost, all properly designed systems include a switchgear.

Hydro:  Hydropower is not new to the state.  Juneau’s Annex Creek plant has been operating since 1915.  Many other hydro projects in Alaska provide clean energy for nearby communities.  Commissioned in 1991, the Bradley Lake Hydro Project near Homer taps alpine Bradley Lake via a 18,610 ft long tunnel that funnels water from the lake at 1,080 ft to a powerhouse at sea level, producing the cheapest energy along the Railbelt in Alaska (Johnson, Chow, Hickey, 2002).  The Railbelt power system in Alaska is unique in that it is electrically isolated from the larger power grids of the Lower 48 states.  Adding to this isolation, Bradley Lake is connected to the rest of the system by a single 115 kV transmission line which is occasionally interrupted and electrically islands the Kenai Peninsula and cuts off the rest of Alaska from Bradley Lake’s cheap power (Johnson, Chow, Hickey, 2002).  Eklutna Lake supplies 10-15% of Anchorage’s power and the city of Gustavus now receives all of its power from the new Falls Creek hydro project that opened in July of 2009, bringing electric costs down from 39 cents a kilo-watt-hour (kWh) to under 20 cents per kWh (Forgey, 2010).  Energy storage is not limited to electrical battery systems.  Because islanded systems are so susceptible to peaks and lows, in many situations wind power is inadequate to provide sustained voltage and frequency.  Hydro reservoirs also afford considerable energy storage which can be tapped to fill the gaps that wind power can leave but by having both technologies working together decreases the risk of production deficits (Brown, Pecas Lopes, & Matos, 2008) (Denault, Dupuis, &Couture-Cardinal, 2009).

Geothermal:  Alaska has more geothermal energy potential than any other state.  In interior Alaska, a few geothermal features exist which may be tapped for energy.  The importance of embracing all forms of renewable sources to create a flexible system is paramount (Blarke, & Lund, 2008).   Geothermal energy adds to the energy diversity of Alaska; however it is ranked lowest in terms of sustainable development relative to the other renewable technologies of wind, hydro, and photovoltaic (Evans, Strezov, & Evans, 2009).  The only hot spring which has been tapped is Chena Hot Springs, and all of the resort’s power comes from the hot springs.  The greatest challenge for geothermal power lies in the temperature of the hot springs.  With a moderate to low temperature of water seeping from the hot springs, it is more difficult to extract energy.  Chena Hot Springs Resort operates at the lowest temperature of any geothermal plant in the world (Chena Hot Springs).

Home systems will also play an important role in providing energy for specific communities.  While a community may perhaps be inadequate for a utility scale wind system, a single home perched high on a ridge line may have perfect access to high winds ripping across the ridge which could spin a small 5 or 10 ft turbine.  If every home had some kind of renewable system either tied into the grid or just dumping heat into the home, large utilities would have to produce less.  An even simpler option is just to build homes and buildings more energy efficiently.  If a certain building is extremely insulated it will naturally require less energy to heat, and large sun facing windows would reduce the need for artificial lighting as well as allow heating through solar radiation.

Economic feasibility is the issue that looms over every energy project.  Coal is cheap to mine and there is a large infrastructure built around it, which is why the technology has not been immediately replaced.  However, as coal-fired power plants age and replacement is in sight, renewable sources are primed to step in and fill the void.  The solution is not composed of a single technology.  The solution to the energy demand of now and the future will be a gracefully connected system of hydro, wind, geothermal, solar and improved building techniques.  Because of its size and unique environment, Alaska and its communities is a perfect proving ground for renewable energy technologies.  Clearly, the forty-ninth state is extremely active in the movement towards cheaper sustainable power.

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