The criteria for choosing a place to install wind turbines are the size you envision, the power you wish to produce, the number of turbines and the regular presence of wind. The efficiency of a wind turbine depends on its placement. The capacity increases in proportion to the speed of the wind cubed. For this reason, sites are determined by the local wind speeds: a site with winds averaging 20 mph will be eight times as productive as a site that averages 10 mph. The consistency of the speed and wind direction are two other important criteria for choosing a site. In fact, as a general rule, wind turbines can be used where the wind speed is above five and below 55 mph, a speed beyond which turbines must be disengaged in order to limit damage and the risk of breaking. The turbine’s axis of rotation should usually be kept parallel to the direction of the wind. Certain sites close to obstacles (trees, buildings, complex escarpments, etc.) should also be disallowed because the wind there is too turbulent. You should know that wind turbines become less effective at high altitudes because the air is thinner. At 3,200 feet, the product of a wind turbine will be 10 percent lower than at sea level. Finally, note that certain specific sites increase wind speeds:
The sea or lakes are favored spots since there are no obstacles to the wind. Thus, even at low altitudes, winds are faster and less turbulent. The nearness of an escarpment, on the other hand, will create turbulence and cause wear and tear.
When air rushes in between two obstacles, such as two mountains or buildings, it accelerates; the same occurs when it reaches the top of a hill. So these places are very appropriate for wind turbines. However, the surface area is usually very limited and can be subject to turbulence.
Wind energy can be very powerful in certain cases, especially in wind parks at sea, which can generate hundreds of megawatts but cannot function under all conditions. Denmark, the uncontested world champion of wind power, only produces 20 percent of its electricity through such power. In practice, the electrical power yield represents between 20 and 40 percent of installed power. On the other hand, a small wind turbine, individual or domestic, with a power up to 100 kWh, can be very useful. In this case a wind turbine, connected to a network or even an autonomous turbine in an isolated spot, can be used to produce electricity and run electrical appliances (pumps, lighting) in a permanent manner, especially in a rural environment. For example, a small wind turbine equipped with a solar photovoltaic module and a battery pack can guarantee the energy autonomy of a sailboat (lighting, instruments on board), which makes possible a marine SAB. In any case, you must take into account that the actual yield of your wind turbine will be far inferior to its theoretical yield. If it has a theoretical optimal yield of 100 kWh, you should count on the average production being between 20 and 40 kWh.
In cities, where it is difficult to get powerful air currents, smaller equipment can be used. Roof wind turbines—which are generally small or medium capacity (up to 6 kWh, what your old refrigerator consumes) and specially designed for urban environments—allow you to mitigate routing problems and palliate electrical outages, but produce only a modest amount of energy. Small installations can be fed by a portable wind turbine, which can be useful, e.g., on board a boat.
Armed with these basic notions, you must now determine the wind potential of your SAB. If your SAB has a lot of space available, and the winds are constant and fairly strong, choosing to use a wind turbine can be very valuable. You must study the winds: determine any possible sea breezes or land breezes (in daytime, wind tends to flow from sea to land; at night, it is the other way around), and the different air flows found in a valley (hot air tends to rise during the day, while the cooled air flows down into the valley at night). Study regional winds like the Scirocco, Bora, or the Mistral in Europe, Chinook, Diablo Norther, or Chubasco in the Americas, Brickfielder in Australia, etc. If the wind is too violent, it is not useful. Consult meteorological statistics, talk to people who have lived in the region a long time, arm yourself with a map, climb to the most elevated spot you can find and make observations. Figure out what possible obstructions there might be to the wind (e.g., buildings, trees, and especially hills and mountains). The best spots are usually beside the sea and crests that always face dominant winds. Finally, and this is important, inform yourself about any building restrictions, especially environmental and zoning laws. Talk about your project with the neighbors and be open to their objections in order to avoid making enemies (people often react negatively to wind turbines, which they consider damaging to the landscape, noisy, or even harmful to animals or to health). In any case, it is not easy to get authorization for a small wind turbine (i.e., one-to-five meters (three to 15 feet) in diameter with a yield of three to 40 kWh). For large properties (farms, ranches, etc.), it will be much easier to get authorization; in this case, a wind turbine 10 meters (30 feet) in diameter, generating between 40 and 200 kWh, can be an excellent solution, if wind conditions are favorable enough. Also note the frequency and complexity of repair work, since a wind turbine waiting to be repaired does not produce any electricity. So carefully study the lifespan of the parts most subject to wear. Inform yourself about the possibilities for reselling excess production to public authorities; this could allow you to cut your own costs and make a profit on your investment.
To summarize: wind can be a good source of energy if conditions are favorable, but it cannot be your sole solution, since winds can die down for several days at a time. It can be useful for the inhabitants of a valley or small region to form a group and install a wind park to meet some of the local electricity needs. A wind turbine with 20- to 30-meter (65 to 100 feet) blades costs between $400,000 and $520,000, and can generate enough electricity for 100 to 200 households. Volume also allows one to employ specialists, who are dedicated 100 percent to such sources of energy and maintaining and repairing the equipment involved (this is almost impossible to do on an individual level.) Thus, a wind park could be a strategy for transforming a village or small region into a super-SAB. We’ll talk more about that later.
Solar Energy
Energy radiating through our atmosphere directly from the sun will be useful to us. It can be caught by solar panels, of which there are two kinds:
thermal solar panels, called “solar collectors,” trap the heat of solar rays and transfer it to a fluid medium;
photovoltaic solar panels convert light into electricity. Photovoltaic solar power is commonly called PV.
In both cases, the panels are usually flat and about one meter square in size in order to keep them easy to install. Solar panels are the basic equipment for producing solar energy. Thermal collectors are more efficient and profitable at the moment than photovoltaic modules. Their price is much lower, and they yield around 50 percent, even if the energy they allow to be recovered is obtained in a less valuable form (hot water at a sterilized temperature instead of electricity). Thermal collectors are just as profitable in northern latitudes (Northern France, UK, Belgium, Canada, etc.) as in sunny regions (Spain, Italy, Texas, Florida, New Mexico, Australia, Tunisia, etc.). On the other hand, photovoltaic panels are only profitable where there is no electrical grid, unless they are subsidized in some way. You must inform yourself thoroughly about the possibility of selling your excess solar-generated electricity to public authorities. You must know that only 10 percent of solar radiation is transformed into usable energy (electricity). Although profitability is not our primary concern, it is a point you must keep in mind in order to choose the right project. In mountainous regions and those with heavy snowfall, solar panels can be inclined up to 60 degrees to allow the snow to slide off. The warm surface of a sun catcher will quickly melt any remaining bits of snow. (I can confirm this is the case, as I have roof installation on my mountain farm.)
Thermal solar panels (“solar water heaters”) are panels in which water or another fluid medium moves in a closed circuit through tubes equipped with blades. To get the best yield, the whole ensemble is placed in an insulated glass box, which permits a sort of greenhouse
effect. With significant sunshine, and if your need for hot water is moderate, a simple tube network can be sufficient. The fins, which form what is called an “absorber,” are heated by solar radiation and transmit their heat to a liquid medium which circulates in the tubes. Solar water heaters are used to produce clean hot water in a solar hot-water heater. For now, this is the most profitable solar-energy solution. Combined solar systems are starting to be developed, with the goal of producing both clean hot water and hot water for heating a house. Such systems allow savings on the order of 350 kWh per year per square meter paneling.
Photovoltaic solar panels are made up of small photovoltaic cells connected to each other. They can be installed on fixed supports or mobile systems that move to face the sun. In the latter case, electrical yield increases by about 30 percent compared to a fixed installation. Outside solar-power stations, fixed installations are found mainly on the roofs of houses or office buildings, either integrated into the roofing material or superimposed. In certain cases, panels are installed vertically on the facade of buildings, although this inclination is not optimal for producing electricity. Portable solar panels can be useful for camping or on trips; plan on having some in your SAB.
The principle by which current is obtained by the cells is called the “photoelectric effect.” These cells produce direct current from solar radiation. The use made of the current differs from one installation to another according to purpose. Two types of use are worth distinguishing: where the photovoltaic installation is connected to an electrical network and where it isn’t. Non-connected installations can directly consume the electricity produced with battery accumulators, in order to dispose the electricity during periods without light (night, blackouts, etc.). Photovoltaic installations connected to a network inject the electricity they produce directly into the network. To do this, installations are equipped with alternators that transform the direct current to alternating current according to the characteristics of the network. This does not require installing storage batteries. The electricity is consumed the moment it is produced by the closest devices on the network.
It is also possible to configure a system connected to a network, but which also has batteries in case the network goes down. The value commonly used to calculate the capacity of a solar panel is one kWh per square meter of panel exposed to direct sunlight. In practice, the energy coming from the sun depends upon the latitude, cloudiness, the inclination of the sun (which determines the density of the atmosphere that light must cross), and thus the hour of the day. In the course of a single day, even without clouds, the electrical output of a panel varies constantly as a function of the sun’s position; it is only at its maximum during midday, for a short period. It is just at this time of day that you have the least need of electrical energy, and if you cannot store the electricity produced in a battery, it will be lost.
The quality and lifespan of your solar panels vary considerably according to whether they are of the mono-crystalline or poly-crystalline type and according to the quality of manufacture. A high-quality solar panel, which is more expensive, can last more than 30 years.
What is the solar capacity of your SAB? As a function of your geographical position (latitude, altitude, climate) and orientation, you will have greater or lesser exposure to the sun. Cloud cover is also an important factor, since it diminishes the efficiency of solar panels: some regions are very cloudy, others get a lot of fog, smog, etc. Watch out for places that can get violent gusts of wind, as panels can be torn out of the ground.
If you want to cover all the needs of your SAB—35 kWh in our example—you will have to install at least 35 square meters (375 square feet) of paneling. If you obtain 80 percent efficiency, you will need to add another seven square meters (75 square feet) for a total of 42 square meters—which would make for a rather large roof. The good news is that in spite of their rather high cost, photovoltaic solar panels are easy to install. But even if you have covered all the roofs in your SAB with panels, you will still have a problem: at night, when there is no more sunlight, you will not have any electricity. So you must consider batteries, which are very expensive, or keep plugging in to the public electrical grid, which defeats the purpose of full autonomy. A hybrid solution, like the one I have, would be to have photovoltaic panels plugged into the grid and have batteries as backups that you connect in case the proverbial shit hits the fan, and the grid goes down.
Heating
“Central heating” means that several rooms of an apartment or house are heated from a single point thanks to a heat generator, i.e., the boiler, and with the help of various forms of energy such as wood, coal, gas, heating oil, etc. To do this, you install one or more boilers in the boiler room according to the needs of the facility in question. In most cases, the boiler is connected with piping to radiators or convection ovens placed in the rooms that need heating.
Given the kind of future for which we are preparing, heating with gas, coal or heating oil seems like it would be heavily compromised over the long term. If the boiler in your SAB is old or inefficient, this is perhaps the time to replace it with something longer lasting. If your SAB is close to a forest, why not heat it directly with wood? This is a much cheaper solution than heating oil. In any scenario, the good old wood stove in the main room remains an excellent solution for the winter, since it heats efficiently, especially in the case of an isolated home. Hence the importance of effectively insulating the living spaces of your SAB. Be careful not to heat your house to the point where it turns into a sauna, and you are forced to go around in shorts and flip-flops in the middle of winter—which happened to me in an overheated apartment I once lived in. Lower the temperature to 66 °F (19 °C) instead of the usual 70 °F (21 °C) and dress normally. Do not overheat your sleeping quarters: people sleep better at a cool temperature (and in times of crisis, you will probably want to snuggle with the wonderful creature who sleeps with you). For bachelors, there’s always the water bottle! A temperature of 63 °F (17 °C) or 64 °F (18 °C) should be acceptable. At my farm, for example, I don’t heat the bedrooms, so that we sleep in winter at 15 °C (59 °F), but that’s also because the walls are well insulated from the sub-freezing temperatures of the outside, and because the wood stove in the main living room radiates quite efficiently. In general, err on the cool side and put on a sweater if you are cold.
For auxiliary heating, why not plan on having a heat pump, which can take the heat from the air, water, or ground and release it in the places where it is needed?
As with all your projects, find out if there are possibilities of receiving subsidies or tax exemptions in your region or country. Use all means allowed by law to economize, while you still can. And if you do not care about the savings, you can always send me the excess money.
Cogeneration
Cogeneration means producing electricity and heat simultaneously, with heat being a by-product of electrical production, or vice versa. Generating electricity usually releases a great deal of heat, which dissipates into the surroundings. Cogeneration allows this heat to be channeled into heating buildings, sterilizing water, etc. The electrical energy is either consumed or put back into the public grid.
Let us take a practical example. In case your SAB simultaneously needs electricity and heat:
a classic configuration could be a heating-oil boiler in conjunction to electricity coming from the grid;
a cogeneration configuration would be having that same boiler generate electricity, while you use the heat for heating the house. Electricity can also be generated by solar panels (to heat water and produce electricity) and other renewable sources.
Batteries and Candles
Look around you: how many things do you see that run on batteries? Flashlights, surveillance equipment, computers, Geiger counters, etc. Stock enough rechargeable batteries of all types and get some chargers, including those that operate on solar power. It is better to overestimate your battery consumption. According to the U.S. Army, lacking
a sufficient number of batteries is one of the major problems of modern armed forces. You will consume a lot of them—quickly.
If you have chosen an electrical system that stores electricity in batteries, handle them with great care; they are potentially dangerous objects because of the electrical charge they contain, but also because a battery is filled with acid (lead batteries, for example, actually contain sulfuric acid). You will have to stock empty batteries for recharging (without acid, which should be stored separately and safely), so as not to use up your batteries too quickly.
Stock lots of candles in all sizes; you will need them. A good-quality candle can be kept indefinitely, and short of learning how to make them yourself—which is not a bad idea—your supplies can serve you for a long time, or be useful as items for exchange.
I am often asked if it is necessary to acquire a diesel generator. This is certainly a very useful machine, especially if you get one able to generate between four and 10 kWh, since it can supply you with electricity if all your other systems are down. But how much gasoline can you store anyway? Besides, a generator is very noisy and thus, in urban environments, can attract a lot of unwanted attention during bad times. It is a good auxiliary solution in the medium term, but certainly not over the long term if oil scarcity accelerates.
I do not know if an ideal system exists to cover the energy needs of your SAB. In any case, it seems logical that if you reduce your needs and consumption, and, at the same time, install an efficient system for generating heat and electricity. You can arrive at a reasonably affordable result that will last a long time and, perhaps, even be totally autonomous.
Do not hesitate to ask for advice from energy specialists. Have them explain the different options for your SAB, get a few estimates, go into detail and distrust rough estimates. For the installation, unless you have a lot of experience yourself, work with an electrician who knows how to manage everything connected with electricity. It would be stupid to burn down your SAB because you left some wires uncovered. . .
Survive- The Economic Collapse Page 29