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What is Green and what does it mean? Of course it is a color, in the modern context it means “Earth Biosphere Friendly”. Green has meant in the past “Money”. It has also meant “New, Fresh and Unskilled”. And how about “Nausea” or “Extreme Fear”? Maybe it means saving the world from “Global warming” to some. To me it means “Energy Efficiency” in architectural design of buildings and “Saving Money” each month on energy bills. It can mean reduction of monthly living cost. It can mean a measure of independence gained. It can mean measure of sustainability. But not without a cost. Not without investment.
I have looked into various types of green building. Earth, Straw, Insulated Concrete Forms, Masonry and Concrete, to name a few. Underground, Earth Covered and Passive Solar shelters, to name architectural designs. Some energy efficiency features are “Passive”, meaning they require no effort and no energy consumption. Others are the opposite, “Active”. Some features may be operated manually, while others automatically.
Warning this is a concept design that has not been fully engineered.
Is dirt really “Dirt Cheap”? Maybe, maybe not. Earthen structures may require more labor, however less skilled labor and less complex design. Some types of earth structures and straw bale structures are susceptible to damage from moisture and water more readily than conventional materials. Proper waterproofing will raise construction cost and complicate the design. Automation control will increase cost and energy use in any active systems. Green features will increase the initial cost, overall cost and possibly complicate the design.
How much extra cost there are will depend on the individual builder, the location, the situation, the feature and the day and time. How soon energy efficient features will pay for themselves is highly situational dependent. Obviously on the North American continent these types of homes pay off more quickly in the arid Southwest than anywhere else. But one thing is for sure. A dwelling can be made to be far more energy efficient than the typical conventional dwelling. Monthly energy use can be reduced. In the end its up to the individual to decide if it is worth it or not
There are about 4 factors that make a dwelling more energy efficient than the traditional insulated box (a mere refrigeration unit).
- Use the sun a lot more for heating in winter.
- Use the earth a lot more for heating in winter and especially for cooling in summer.
- Use heavy insulation in the ceiling area.
- Use thermal mass as a storage medium for heat or lack of heat(cold). (This is the most important feature.)
Thermal mass is to heat what the battery is for electricity and similarly it is charged and discharged. The good news is that unlike chemical batteries for electricity thermal mass usually doesn’t go bad and need replacement. Thermal mass would basically be any dense material. Metals work best but are are very expensive for this purpose. Water works great. Earth, concrete, brick and stone are more reasonable choices. Where do you put this thermal mass? Mainly the walls, very thick walls. Could also be in the roof as in a roof pond. Or barrels of water placed here and there. The floor could serve as thermal mass as well.
You can do the math. One BTU is the heat needed to raise one pound of water one degree Fahrenheit. 100 gallons of water (8 pounds per gallon) raised 1 degree is roughly 800 BTU. In space solar intensity is about 450 BTU per square foot per hour. On earth when the sun is shinning bright on a surface which is perpendicular to the sun near the noon hours a surface will receive about 350 BTU/hr. This varies and can be much less in winter as low as 100-250 BTU/hr maximum for during the day. But lets say you have a surface that is 10×10 or 100 ft2 and it is receiving 100 BTU/hr then it gains 10,000 BTU in that one hour. To raise one cubic foot of air one degree F, you need roughly 0.018 BTU. A 10 foot by 10 foot by 10 foot area of air is 1000 cubic feet. Raise that area one degree and that space has gained 18 BTU. A typical window A/C Unit might be rated for 5000 BTU/hour. A typical home heat pump might be rated for 1 ton (12,000 BTU/hr/ton). A kerosene floor shop heater might be rated at 150,000 BTU/hr. The question that I have is, how fast would a given type of thermal mass absorb or radiate heat? I don’t know the figures here, but I assume that would be based on the specific gravity (density) of the material. How much total absorption would also be based on the surface area of the material or its container.
There is more to the overall design than this. Auxiliary heat and cold air may still be needed. De-humidification may also be needed. Vents, and Sky lights may have some positive effects if used properly. Extra shading, operable shutters, curtains, and movable insulation may be needed. Reflectors may help with solar gain. And in the end some of this may require manual adjustments to be economically feasible. Automation is not without additional cost.
Now, on a sad note, our system for getting green houses(or any houses) built and insured may not support all of the green features, or even the entire project. Building Codes may restrict what can be done if your building site is not located remotely where there would be no or little regulation. Insurance may not cover extra cost of the extra features. The market may not accept the extra features. And banks may not loan on these extra features. Great system huh? Its against energy efficiency! Not by design however. I feel that it has simply evolved that way.
In conclusion I say that I feel it is worth it to consider every energy saving feature that could possibly be available to the home owner and even worth reconsidering upgrades over time. If you really strongly desire a truly energy efficient home, build it with cash as you go. You may have to go to some extremes to be able to do this, but in the end any savings you might achieve from owner building and using cash as you go will more than make up for the extra cost of the green features. This also means that as you build it and begin to live in it, you get savings in your pocket immediately. It pays off right away. As an investment that you can liquidate, the picture might not be so pretty. A home that is too far from conventional design and from what the general market expects may be hard or impossible to sell or be sold at a loss. That said I still feel that it is worth considering as long as you use cash and not credit for the construction. For example it could always be rented and with no debt against it, it would mean low overhead and good income.
Oh and my opinion when it comes to power production and the green scene? I am for Solar, Wind, Hydro and Nuclear, and against all other forms of commercial power production except in emergencies or periods of peak demand. I feel that its a great waste to use coal or gas for power production. And nuclear has actually proven to be very safe. Sure we have this depleted uranium problem. But the truth of the mater is that our transportation system is far more destructive to human life and the environment than nuclear power will ever be and you don’t see the environmentalist winning about it? They drive their cars don’t they! Nuclear as far as I’m concerned is a green power technology. The demand for power in the world is only going up and nuclear is the only one that can fit the bill. Fusion power is just around the corner though. I hope to see that in my lifetime.
Great, just as I say Nuclear is a green power tech Japan has an earth quake and tsunami which washes out a nuke plant. The worst of what happened was the spent fuel pools being washed. Generators that power pumps went offline and cause cooling water to stop flowing. This caused the water in the pools to boil dry. Partial meltdown of reactors and spent fuel has occurred. The reactors are designed to contain a full meltdown. They are designed to spread out molten fuel to a degree in which it either cools down completely or enough so that it doesn’t burn through the concrete and deeper into the earth. The spent fuel pools are not under this containment. My question is why not? I would guess because of expense. Lets hope this incident does not do a lot of damage. The media has been saying that radiation has been found in water, fish, milk etc. But this isn’t exactly right. Its contamination, which causes radiation. If something is hit with radiation and the radiation is removed then that thing does not emit radiation and is not radioactive. Unless it is contaminated with radioactive particles. Radioactive particles move around via air and water. Contamination is like a radioactive dust. So they are not detecting “radiation” in food and water but contamination which emits radiation. Even with this scare if you looked into it, you would see that the nuclear industry has a great record for safety. I am thankful that concerned people monitor it closely. We just need to spread this kind of concern to everything else in life.
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