Wind Generated Hydrogen to Fuel the Dining Hall
The Columbia River Gorge is a windy place, so much so that the gorge is considered to be one of the world's premier wind surfing areas. The river is wide and swift, and the prevailing wind is counter to the flow of the river, so skillful riders can zip back and forth across the river for hours and never be far from where they entered the water.
However, from the standpoint of sustainability, wind is a mixed bag at best. First of all, it's a mediocre energy source. Sometimes it's there and sometimes it's not, for days at a time. Sometimes it's too weak to generate power, and other times it can gust to the point where it destroys your wind genny.
But the biggest problem with wind is that it takes more than it gives by making it hard to keep housing warm in winter and vegetation hydrated in summer. Given a choice, one is better off without that particular energy source.
Within the context of sustainability, it isn't so much a matter of embracing the good while eliminating the bad, but rather sustainability involves an ongoing process in which you accentuate the beneficial aspects while minimizing the adverse. In our case, we've located the majority of our buildings and gardens in a hollow formed by a ridge that protects us from the prevailing wind. On occasion, an arctic high pressure system will move down into Idaho and nail us from our unprotected south east side, but that doesn't happen very often. Sure is memorable though when it does :-)
While the primary "use" of our ridge is to shelter the community from the wind, it also makes a good location for a wind generator. Even though wind power is not likely to play a major role in our energy mix, it does have some advantages over solar panels, most notably the ability to generate power at night.
The primary problem with wind generation is storage. You get power when the wind blows, need it or not, so the key question with wind power is how to store the surplus energy. Batteries are bulky and inefficient at best, and while the energy is "free," commercial-grade lead-acid storage batteries are expensive and have a limited life expectancy.
In Washington state, we're fortunate to have the option of connecting to the public utility grid and running our electrical meter backwards, and one of the companies that's a leader in inter-tie technology is located in the Seattle area, so that's a viable option for us. Currently, our electrical usage is in the range of $400/person/year, so while that does add up to a respectable amount annually, it's also a lot less than folks are paying per person " out there." Two things are certain: as Windward grows, our our need for energy will also grow, and the cost of energy is only going to go up.
Each form of energy has advantages and disadvantages. The electricity driving the computer you're using to read this operates internally on direct current electricity, but that energy is delivered to your computer in the form of alternating current electricity. The challenges involved in generating energy are just the start; then you have to cope with storage and distribution, each of which have their own issues to take into consideration.
Our dining hall is designed to use as little off-site energy as is practical; our focus is self-reliance, not self-sufficiency. We're not trying to cut ourselves off from outside resources, just to insure that we aren't dependent on them. For us it's all about having options; the more the better.
The dining hall is heated with firewood from our forest, and illuminated by a bank of southern skylights, etc. Even where commercial energy is used, we're not shy about divvying that up either. For example, we use a propane fired cookstove/grill, but bake in a double electric oven. There's a small highly insulated electric water heater serving the hand washing sink in the mud room where folks clean up before lunch, but our primary hot water source is a gas fired on-demand water heater.
Electric water heaters consume energy 24x7 keeping a supply of hot water ready for use whenever. Gas fired on-demand heaters heat the water only when it's needed so they not only don't waste energy keeping water hot, they never run out of hot water.
The most efficient heating gas for most folks is methane, commonly known as natural gas, but pretty much that's only available to folks who live in the city. In the country, folks rely on propane, and while it's a way better heating value than electricity for heating a room or cooking the soup, it's still a fuel that we have to purchase.
Instead of using propane, our goal is to convert the kitchen over to using hydrogen as the primary fuel, and we'll use wind power to produce the hydrogen.
Transporting wind generated electricity from where you can best produce it to where you need to use it is expensive and inefficient. Wind generators need to be mounted on towers that reach up into what's called the laminar airflow, up above disruptions caused by trees and buildings.
To do that, we have a one hundred foot tower that our wind generator will be mounted on. It's a self-erecting tower that stands about twenty-five feet tall to start, but when extended will lift our genny high up above the trees on the ridge.
Even when the tower is fully retracted, the generator is still some 25 feet off the ground, so the tower has a pivot style base which allows it to be laid down on its side so that the generator can be serviced from the ground with both hands without having to use one hand to just hold on.
This is as good a point as any to note that the sort of systems and operations I'm describing here aren't for everyone; folks, even knowledgeable folks, can be injured or even killed working with alternative energy systems, and those who aren't prepared to do the necessary homework and to faithfully follow appropriate safety protocols need to find some other hobby.
Please don't do for renewable energy what Jim Jones did for Kool-aide.
When energy in the form of electricity moves along a wire a portion of that energy is lost in the form of heat as the electricity overcomes the conductor's resistence. In some situations, such as with the element in an electric water heater or an incandescent light bulb, resistance is focused in order to produce the desired effect, but generally speaking, the lower the resistance, the better.
A watt is a unit that measures the flow of energy, and that energy flow can be described in terms of how much electrical pressure (in the form of volts) and how much flow (in the form of amps) is involved.
The formula is simple:
one amp flowing at one volt constitutes one watt,
five amps at one volt is five watts,
one amp at five volts is five watts, and
five amps at five volts is twenty-five watts.
The total resistance that the energy has to overcome is a function of the composition of the conductor and the distance it has to go. The most common conductor used is copper, but aluminium works almost as well, and the larger the conductor, the less the resistance.
We could strive to conduct the electricity produced by the wind generator down to the dining hall, but given the distance involved, some 600 feet plus the extra 100 foot heighth of the tower, the amount of energy lost to resistance would lower the efficiency to the point of the exercise being almost pointless.
Distribution of electricity in the modern world is made possible by a the fact that resistance is determined only by the current flow, not by the voltage: one amp at one volt sees undergoes the same resistance loss as does one amp at one hundred volts, even those the first current involves one watt and the second involved a hundred times more current.
That's why the overhead power lines that bring grid power onto our property operate at more than 7,000 volts. That energy is then "stepped down" to a more manageable 220 volts using a "center tapped" transformer. The center tap is connected to the "neutral" bar in the breaker panel mounted inside your home, while each end of the transformer is connected to one of the buss bars that the circuit breakers are mounted on.
Any circuit mounted between a buss bar and neutral will show 110 volts, and if you connect a circuit between both buss bars, that's how you get the 220 volts that's used to power the electric oven.
So, we could use a step up transformer to jump up the voltage of the energy put out by our wind generator, and thereby cut down on the loss due to resistance over the long trek from the ridge to the dining hall, but once you exceed 40 volts, a whole different set of rules kick in. Below 40 volts, there's no appreciable risk of electrocution; above 40 volts, especially in outdoors, you have to take steps to insure that
the circuit will function safely.
Fortunately, there's a better option: use the energy to power a bank of electrolytic hydrogen generation cells set up at the base of the tower, store the hydrogen in a holding tank, and pipe it to the dining hall as needed.
Solar Powered Irrigation
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