Saturday, January 30, 2010

Friday, January 29, 2010

Why wind?

Any discussion of sustainable energy for the islands has to include other options. There is a lot of non-fossil fuel energy in world. Which might make sense for Matinicus and Criehaven?

First a note about electricity. Most of the technologies below create electricity, which is not directly practicable for transportation, such as fishing boats. For example, 100 gallons of diesel weigh about 700 pounds. To store the same amount of energy in high tech lithium phosphate batteries would require a battery bank that weighs about 22,000 pounds. Using traditional lead acid batteries, the batteries would weigh over 380,000 pounds. So, even ignoring capital cost, life cycle costs (batteries wear out), recharge time, etc., it is pretty obvious most fishing vessels cannot bear the additional weight of batteries. “Plug-in” lobster boats are a very long way off. (So are plug-in cars, but that is another story.) We need to convert the electricity to an energy dense fuel. [see revision comments at end]

Why don't we just build a cable to the mainland? Construction costs would be about $25 million, about the same as the proposed wind turbine/NH3 facility. Assuming we get 20 year 5% mortgage, that will cost us about $2 million per year in interest. Then we still get to pay 15 cent/kwh (Maine average, October 2009) and whatever the amortization of the local grid on Matinicus is. It still would not provide power to the lobster fleet, nor would it provide for other energy needs, such as gas for cooking.

For routine transportation, there are just two basic fuel types available, carbon and hydrogen based. (I am going to ignore rocket ships, portable nuclear reactors, and other sci-fi). The carbon based fuels, such as gasoline, diesel, methane, ethanol, and propane, have most of their energy released by the combustion of carbon (and some hydrogen) in an internal combustion engine, turbine, or boiler. All carbon-based fuels need carbon to be created, obviously. On-island, we do not have significant quantities of carbon available. We do have trees, but they grow slowly. Theoretically we could gasify the trees (and certain other “waste streams”) to make a methane mixture, but we would run out of trees pretty quickly. Sugar cane produces the most fuel per acre today, but that won't work in Maine. Corn (for ethanol) by some reckonings actually uses more energy than it produces, and it doesn't grow well here, either. I'll do some specific calculations some other day.

Hydrogen fuels, such as H2, metal hydrides, and NH3, do not require any carbon to create. Since we do not have large carbon resources, we are essentially limited to hydrogen fuels to produce locally.

H2 (hydrogen gas) has serious problems as a transportation fuel. To have the same energy as 100 gallons of diesel, one needs a 2,700 gallon heavy tank of hydrogen, compressed to 6,000 lbs/in2. For comparison, a SCUBA tank is usually pressurized to 3,000 lbs/in2. Hydrogen has another big problem in that it is extremely susceptible to leaks. Hydrogen is the smallest atom and leaks through fittings that are tight against other gases. Pure hydrogen burns invisibly, so a fire from a leak cannot be seen. Safety manuals suggest using a broom to find a hydrogen fire: wave it over the suspected flame and see if the broom catches fire. Since the hydrogen atom is so small, it tends to penetrate metals, especially steel, and embrittle them, eventually leading to a catastrophic failure. So, pure hydrogen gas is very problematic.

Some people discuss storing hydrogen in metal halides, compounds that can chemically bind hydrogen. I do not know much about them yet, but I have heard they suffer from significant energy density issues. Several of the hydrides react explosively with water. Probably not a good idea for a boat.

NH3 is an effective hydrogen carrier. NH3 actually has more hydrogen per gallon than either compressed hydrogen or liquid hydrogen. Our 100 gallons of diesel would require 253 gallons of NH3. Not great, but still it would fit under the deck on most boats. Boats would not have to carry as much fuel as diesel, since the supply would be local. A fisherman does not have to go inshore or wait for the buyer to deliver fuel.

NH3 is a relatively large molecule, so there are not any special concerns regarding fittings and leaks. While it does not embrittle metals like H2, NH3 when reacted with water is corrosive to copper and zinc. Conversions of engines will require substitution of any copper or zinc in the fuel line. I am not aware of modern engines having any of these metals, however. There would be no change in the use of zincs as sacrificial corrosion inhibitors.

On to other energy options!

Deep geothermal

Extracting heat from deep below the earth's surface has several advantages. The heat is constant, with equal amounts of heat in winter and summer, day and night. The heat is used to make steam which then runs turbines to make electricity. There is enough deep geothermal energy to provide over 100% of the US energy needs. The electricity then needs to be converted into a usable engine fuel, such as NH3.

Unfortunately, the deep geothermal resources in the US are all west of the Mississippi. We are out of luck.

High altitude wind

There are several research projects for putting wind collectors up in the jet stream, over 20,000 feet high. The wind is constantly blowing, often over 200 mph. One design is held aloft like a paddlewheel on a balloon, another is an autogyro, which looks a little like a helicopter. A cable brings the power down. Because the wind is stable up so high, the kite stays aloft and stays in the same position.

The wind blows west to east, so a kite launched from the islands would be flying way out to sea, and not over any other populated places. This technology is said to be 10 to 20 years away. It has been estimated that capturing one percent of the jet stream wind could supply 100% of the global energy needs. We are located in a good jet stream area, so maybe this will be effective for us one day in the future.


Thermal solar, converting solar radiation to steam that goes through electric turbines, has great possibilities. A plot 100 mile by 100 miles in the Arizona desert could produce enough electricity for the whole US, assuming you could get it built with all the little bugs, “environmentalists”, and lawyers in the way. However, last time I checked, we don't have quite as much sun as Arizona, so we are out of luck.


OTEC stands for Ocean Thermal Energy Conversion, which is a technology that takes advantage of the difference in temperature between the bottom of the sea and the surface. In the tropics, surface waters can be as high as 90 degrees, while a mile down the temperature is below 40 degrees. That difference can be used to power a turbine. The potential is huge; tapping one percent of the heat could meet 100% of the world's energy needs. It is highly capital intensive and still in development. Unfortunately, our surface waters are lot closer to 40 degrees than 90 degrees, so it won't work for us.

Waves, Tides, and Currents

This always seems like the obvious stuff to research in the Gulf of Maine. Seeing the surf smash up on Sou'west Point, I always thought waves should be a no-brainer. I discussed this with several researchers, who almost laughed. We actually have very little wave power because a) we are sheltered by Nova Scotia, and b) we are on the East Coast. All the big wave energy is on the west coasts, as the waves build with the wind across the ocean. This is a non-starter.

Harvesting current and tidal power usually requires rather specific geography in order to have high speeds. The Minas Channel in Canada and Passamaquoddy Bay have some interesting opportunities which are being developed. The total energy from these projects is not as large as you might expect. Neither project, at full development, will produce enough power to satisfy all the state (or province) electrical needs. One of the biggest challenges for any of these tidal current projects is survivability. The devices need to be light enough to produce power on normal summer days yet need to survive winter storms.

Our geography does not lend itself to ocean water-produced electricity, and I doubt we will ever have effective technology to harness our tides.

And that leaves...

Ground-mounted in-water wind turbines to make NH3, unless someone has a better idea. NH3 will probably be the fuel of choice even if other means of capturing energy is used, such as high altitude kites. Suggestions and discussion welcome.

Monday, January 25, 2010

Matinicus Rock weather station to be fixed!

Finally! NOAA will install a temporary weather station on the Rock in March. We can get back to tracking wind and weather conditions.


More information on Wind Turbines

Some people have questions about the size and looks of a turbine.

Here is a picture of a pair of turbines in the water. These are in Europe.

The base is about 20 feet in diameter at the waterline. The hub height would be about 300 feet high. This type of construction is called monopile. Basically a huge pile driver drives in the base, then the tower and turbine are mounted on top. I have been told it takes less than a week to install one.

Here is a diagram of foundations:

Note the monopile is used up to 30 meters (100 feet) depth. Driving in the pile is the cheapest way of installing a turbine. I suspect our bottom is too hard, so this may not be practical. In that case we would use a gravity style base. A gravity base is the most common foundation for in-water turbines.

The "tripod" style base is for deeper water, and would probably not be an option for us.

Two issues that will certainly come up, so they must be discussed: noise and flicker.

Aren't turbines noisy?

Honestly, I do not know yet. Most public specifications about turbines show that the noise generated is less or about the same as ambient. In other words, when the wind is blowing 20 knots, there is a lot of other wind noise from trees. Certainly around the islands the surf is very noisy on windy days. Fishing boats are much louder.

On the other hand, there are a lot of people on the Internet complaining about turbine noise. Certainly a few of the folks on Vinalhaven are upset about the noise. When I visited Vinalhaven the noise was minimal, but it was not windy when I was there.

There are ways to mitigate noise by detuning it for certain wind velocities and directions.

We, everybody in the community, have to learn about the noise issues firsthand and decide if these are insurmountable issues.

Isn't flicker a big problem?

Unlike noise, flicker is not a serious problem. Flicker is the shadow caused by the spinning turbine blades. Flicker can only happen on sunny days near sunrise and sunset. In the middle of the day the sun is high so the shadow is very short and close to the base of the turbine. Flicker can never happen to the south of the turbines (in the northern hemisphere). Flicker does not happen for a long time since the shadows move with the sun. If a house was in the shadow of our turbines (rather unlikely since the turbine will be in the water), the exact time can be calculated, so on sunny days (there is no flicker or shadows on foggy days) a turbine could be stopped for a few minutes on a few specific days until the house is out of the shadow.

Flicker gets a lot of play on the Internet because it is very easy to make a dramatic YouTube video. I do not think we will have any issues with flicker.

Tuesday, January 19, 2010

Matinicus and Criehaven Sustainable Energy System

Our islands have several challenges in maintaining sustainable communities. Energy is expensive, and will almost certainly get more expensive. I estimate the two islands spend between one and two million dollars a year for energy – diesel, gasoline, heating oil, propane, and electricity. Over the next 20 years, if energy prices do not go up much, we will be spending about $40 million. And we are sending a lot of that money to people who don't like us.

We are lucky to be in a Zone 6 wind area, which the Department of Energy calls “outstanding”. If only we could use some of that wind to meet all our energy needs....

NH3 (anhydrous ammonia) is a potential fuel. It can be used in internal combustion engines with some modifications. It could also be used as a propane replacement for stoves and heaters. It burns to H2O (water vapor) and nitrogen gas, and has no greenhouse or ozone-depleting effects.

NH3 can be made from air, salt water, and electricity. If we have some powerful wind turbines, we could use the electricity to make NH3 and power the Matinicus grid. When the wind is light, we use some of the NH3 in a generator to make electricity. Most of the NH3 would be used as fuel for the lobster fleet, and some could be used for other purposes, such as cooking. In the windy winter, when there is a lot of electricity, some of the (excess) electricity can be used for heating economically.

I estimate we use about 400,000 gallons of fuel a year. Ten percent of that is used for producing electricity on Matinicus. We would need between four and five megawatts of power to produce the equivalent of 400,000 gallons of fuel. For comparison, the Fox Islands Coop's three turbines have a capacity of 4.5 megawatts.

The Fox Island project cost about $15 million dollars. A rough estimate of an NH3 plant is about $10 million, so the total might be $25 million. That sounds like a lot of money, but so is the $40 million we will probably spend over the next 20 years.

A wind-turbine NH3 facility would essentially lock in our energy cost for the next 20 years. My very rough figures indicate an equivalent cost of about $3.00/gallon for NH3 production, so in the very short term we would not be saving money. However, almost all the cost of production is fixed, so in ten years, the cost would probably be only $3.30 per gallon, and in 20 years $3.60.

Predicting future energy prices is a crap shoot. My forecast is that energy will be going up for several reasons.  1) “Peak oil” theories strongly show that we are not discovering new oil supplies nearly as fast as we are consuming them, and that we are using up the easy-to-refine, easy-to-pump resources. Some people say that Saudi Arabia may be a oil importer by 2035.  2) The US is the only oil importing country with the price of gasoline under $5.00. Gasoline has been over $5.00 in Europe for a decade. I do not see any way we will be able to continue with cheap gas.  3) Washington is intent on raising the cost of fossil fuels, whether by cap-and-trade, carbon taxes, or other mechanisms.  4) The US dollar will suffer from significant inflation, so the price of oil will rise as other countries, like China and India, buy oil with strong currencies.  5) Petroleum is heavily subsidized in the US. See my posts about subsidized petroleum at l below .  The true cost of oil, without subsidies, is over $5.00 per gallon. I doubt that the country will continue to afford such a cross subsidy in the future

My guess is in ten years we will see ten dollar gasoline. Your guesses will vary. However, I don't think anybody sees $2.00 gasoline on the horizon.

I am researching the possibilities of setting up a system for us. We would be the first people doing this kind of project. I will be talking with everybody from both islands to get questions, and hopefully get some answers, too.

FAQ – the Frequently Asked Questions

What is NH3?

NH3 (anhydrous ammonia) is a very pungent, colorless gas that is lighter than air. When exposed to water, it becomes ammonium hydroxide, NH4OH. Ammonium hydroxide is what we commonly know as ammonia in household cleaners.

NH3 is one of the most produced chemicals in the world, with over 120 millions tons (48 billion gallons) consumed annually. Most NH3 is used for fertilizer; half the world's food is produced with NH3 fertilizers.

NH3 handles very similarly to propane. At 115 pounds pressure it is liquid, and is stored in low pressure tanks, just like propane. Some users actually use propane tanks for the gas, but that is not recommended.

The Department of Transportation considers NH3 non-flammable, as it has a very high ignition point. A typical lighter cannot ignite it. NH3 is virtually impossible to cause an explosion at normal pressures.

As a gas, the fuel is always kept under pressure in a closed system, like propane. Unlike propane, a small leak is very noticeable, and the gas floats up and away.

Turbines are big. Where would we fit them?

Obviously there is no room on-island for turbines. They would be in the water, probably on the western side where there is less wind shadow. A solid state NH3 synthesis plant should be able to fit inside the tower itself. I am proposing two big turbines to minimize the disturbance to the bottom.

What about the fishing bottom?

Obviously, nobody wants to do anything that threatens or hurts the fishing bottom. We need to do careful studies and research to make sure nothing we do will harm the fishing.

Some fisherman have asked about the electricity in the water. There have been buried underwater cables for years all over Maine, such as Vinalhaven, North Haven, Isleboro, and Isle Au Haut. I am not aware of any complaints from fishermen in these areas. The cables for the turbines would all be buried below the bottom, so traps can be set without interference.

Isn't NH3 toxic?

No. Most animals, including humans, produce NH3 naturally, and excrete the excess. However, NH3 is highly caustic, and too much can cause serious eye and lung injuries, including death.

All fuels are potentially dangerous. Propane, natural gas, and gasoline vapors are highly explosive. Gasoline causes cancer and dermatitis. Diesel creates long-term pollution when spilled and does not bio-degrade. Diesel usually has smoky exhausts. All carbon-based fuels emit carbon dioxide, and the liquid fuels emit other pollutants such as NOx, sulfur compounds, and carbon monoxide.

NH3 is detectable (intense smell) in very low concentrations, about 5 parts per million, which is way below any dangerous level. Unlike propane, NH3 leaks are not ignored.

The technology for storing and distributing NH3 is well known and understood. Everybody who works with NH3 will receive appropriate training. The safety record for NH3 is very good. More people die from lightning and personal watercraft accidents than NH3 exposure.

Is this an Island Institute project?

No. I have had conversations with several of the Island Institute people, but this is not an II project. This is an islander project. If we want to do it, we will. If we do not want to, we won't.

Coincidentally, I went to Harvard Business School with George Baker, who has been driving force for the Fox Island wind project at the Island Institute.

How does NH3 work in an engine?

There are half a dozen ways to burn NH3 in internal combustion engines. During World War II, the buses in Belgium all ran on NH3. The US military did a lot of work on running tanks and other vehicles on NH3 in the 50s, in case there was a war and a shortage of oil.

NH3 has such a high ignition point (1204 deg F) that normal compression ignition (diesel) or spark ignition (used for gasoline engines) does not work. An igniter is needed, such as diesel fuel, hydrogen, DME (dimethyl ether), or propane.

One way of running NH3 is to start a diesel engine with diesel fuel. After the engine starts, a steady supply of diesel fuel is injected to keep the engine idling. When additional power is needed, NH3 is injected into the engine. This process works with about 90-95% NH3, and the balance diesel. One big advantage of this type of system is that if there is a shortage of NH3 or some other problem, the engine still runs fine on 100% diesel just by turning the valves.

I will be happy to explain some of the other means of running engines for those who are interested.

Who is going to own this?

This project will only work if it is community-owned. Whether or not the entity will be actually a co-op or another legal form has not been determined. It will not be a part of the Matinicus Plantation Electric Company, however the project will have a power purchase agreement to supply electricity to the co-op.

Will we vote on it? How long will this take?

Yes, when there is enough information there will be a vote. This project will only move forward if the community is very strongly in favor of it. If only 60% say “Yes”, this project won't happen.

I am still gathering information, and I do not have all the answers yet so there is nothing to vote on at this point. Please send me questions or comments. The best way is to put them on this blog, or you can email me. Please click on the link below.

If we get information that shows this project is feasible, and if everybody is strongly in favor, the project will take four to five years.