Thread: ECO HOUSE

What I am trying to do is compile as much information as I can before investing my hard earned money.

If you don’t have something constructive to say go elsewhere.

Solar Cooling - Air Conditioning From the Sun


At first glance, solar cooling looks like an oxymoron. However, the same energy that can provide heat in the wintertime can also provide cooling during the summer.

Several passive cooling systems have been developed and tested. At their simplest, they rely on a coolant that absorbs and dissipates heat from the house. This could be a pool of water on the rooftop which absorbs seat from the inside of the house as it evaporates on exposure to the sun.

More sophisticated passive solar cooling systems have a solar collector which is shaded during the daytime. A storage medium collects heat during the day and dissipates it at night by exposing the solar collector to the cool night air.

Since the solar collector must be shaded, a retractable awning or overhang extension can be installed. Since the system can be reversed in the winter months, it is important that the solar collector can be exposed to sunshine if needed.

Solar panels can also be used to operate traditional air conditioners. As it happens, the periods of intense heat correspond to the periods of peak electricity production from photovoltaic cells. As long as you have solar panels which generate sufficient to electricity, you can operate air conditioners at no cost.

Solar cooling that does not take advantage of high technology is another possibility. The Romans used a system of running water to cool down exterior walls of their houses. The heat of the sun causes the water to evaporate and dissipate the heat within the house. This kind of system can be used on walls or on rooftops.

Heating and cooling are two of the biggest expenses for most households. Using solar energy to reduce this expense makes sense financially as well as ecologically. The less dependent we are on fossil fuels for heating and cooling the cleaner the environment will be.

SUSTAINABLE ARCHITECTURE

As "consumers" we are frequently confronted with life style decisions that can impact our environment. There are a few choices in this life that can make a big difference in what the quality of life will be for those who follow us. Going with the flow of our culture is hard to avoid, and unfortunately the flow is not in the right direction for evolving a sustainable future. One of the most momentous choices that any of us will make is the kind of house we live in. I have come up with a list of thirteen principles of sustainable architecture (listed as links on the left) that can guide you in your housing choices.



USE RENEWABLE ENERGY

There are many ways to conserve the use of fossil fuel; using the sun, wind, or water to produce electricity are among them. If you choose to do this, you will be forced to be careful in the way you use your electricity because it is limited. Whether you get your electricity from alternative sources or from the grid, it pays to choose energy efficient appliances. Front-loading clothes washers, for instance, use much less electricity, water and soap than the top-loaders. Compact florescent lights use about a third of the electricity of standard bulbs. Many appliances use electricity by just being plugged in (known as phantom loads); be sure to avoid this.

Keep Your Cool

A well designed solar house is both warm when you want it and cool when you want it; that is to say, the temperature tends to stay fairly even. A good way to keep your cool is to dig into the earth. About six feet under the earth, you will find that the temperature varies by only a few degrees year round. While this temperature (about 50-55 degrees F.) might be too cool for general living comfort, you can use the stability of the earth's temperature to moderate the thermal fluctuations of the house. If you dig into a south-facing hillside to build, or berm the north part of the house with soil, you can take advantage of this. The part of the house that is underground needs to be well insulated, or the earth will continually suck warmth out of the house.

Cooling Your Property Naturally


Years ago a budding hotelier decided to develop a green boutique hotel from an old building he wanted to renovate. He used hardwood floors and low VOC paints and varnishes throughout, cotton linens, and water conserving fixtures in the bathrooms and kitchen. He opted to use ceiling fans for cooling so that allergens and molds often associated with air conditioners and swamp coolers would be eliminated. Given his location in a dry climate, his idea was feasible. His boutique hotel was beautiful and beautifully appointed. But his two-story boutique hotel was unbearably hot in the summer, a situation that could have been averted � without installing air conditioning � if he'd used a few easy techniques for his cooling, and if he'd consulted Green Builder. He had two lines of defense to help him.



Keeping the heat out of the building should have been his first line of defense. That can be accomplished four ways: first, installing thick, dense insulation in the attic and outer walls; second, blocking the sun from the windows either with a roof overhang, window awnings, or window coverings; third, shading the building; fourth, reducing heat-producing appliances and lights.

This hotelier opted to keep the original bricks and exterior framework. That decision prevented the use of thick insulation so the R value was inadequate to keep the interior cool in the summer. Insulation has improved since this renovation was done. Today, approaches to insulating the exterior walls could have given a high R value without modifying the exterior framework and facade. There are new insulations that give a high R value which contributes to guest comfort; as an added benefit, some don't contain formaldehyde. Dense-pack cellulose insulation is my favorite of what I've seen because of its higher R value, low energy use due to containing high amounts of recycled content, and low manufacturing pollution. Walls with a high R value will go a long way to creating interior comfort for your guests and your staff.

Windows allow about 40% of your heat gain into the building. By keeping the straight, unadorned exterior of the original building design, large overhangs weren't possible. They would have shaded the second floor windows in the summer, keeping those rooms cooler; the first floor windows wouldn't have been helped by four foot overhangs though. Window awnings would have also kept the sun out, and again keeping the rooms cooler, but would have changed the look and feel of the exterior. Exterior solar shades can also be effective in blocking the heat from entering the house. The challenge every architect has is balancing form and function. The form was authentic and original, but didn't help the function of cooling the house. Finding a way of imitating the original design while giving the functionality would have been ideal. Interior window coverings were used for keeping the sun and heat out, but inadequate because the heat was allowed inside before they could do any blocking.

Shading the building was another option; shading can reduce interior temperatures by as much as 20 degrees F (11 degrees C). Being in a congested area with small lots and the need for ample parking limited his options in this approach to keeping the building cooled. Trees are a good way to shade a building; work with your local nursery to select the best tree so you can get the right height, spread and shape to give you your best shading. Vines, grown on trellises which are set away from the house so that air can circulate, also help to keep the building cool. Growing the vines on trellises keeps the plants from attaching themselves directly to the building facade, where damage can be done.

Venting the heat from the building was his second line of defense. Natural ventilation is an option that works best in climates of cool summers or cool nights, breezes being an important aspect of that equation. Open windows and doors and a whole-building fan are good venting options. Creating a chimney-effect where you bring cool air in lower levels of the building, say the basement or first floor, rises as it warms, and exits from openings higher in the building, is a viable passive venting system. Setting up such a chimney effect creates a low pressure system so more air is pulled in through the lower-level openings. Cross-ventilation, leaving doors and windows opposite each other open, is most effective when the ventilation path is long; that may require leaving some doors and windows closed so the air current travels a longer distance, effecting more cooling than a short path would.

The roof allows about one-third of the heat gain in building. Attic ventilation, where you have one square foot of vent per 100 square foot of ceiling space, evenly divided between soffit and rooftop, works to reduce heat gain from the attic. A vented attic can be about 30 degrees F (16 degrees C) cooler than un-ventilated attics. Attic ventilation in conjunction with attic insulation is the best way to block heat from entering the living space and remove heat build up from the attic. Turbine vents are valuable in that they catch any bit of breeze and pull heat from the attic space; I consider them active, natural ventilation � a great benefit without using any electricty.

And finally, whole-building fans are affective in venting both the building and the attic space of heat. The biggest drawback to this approach is that it consumes electricity. Its advantage over natural venting is that it can accomplish the air exchange more quickly.

Of course, reducing heat sources from the inside will help too. Interior heat sources include lighting and appliances like the water heater, refrigerator/freezer, dishwasher, oven/range, and dryer. Vent the utility room directly to the outside to minimize heat transfer into the rest of the building. Buy energy efficient appliances because they not only use less energy but also generate less heat. Convert from incandescent to compact fluorescent bulbs to save energy and produce less heat.

Cooling strategies to consider:
* Walls/Windows
- install awnings or solar shades
- insulate
- plant shade trees and vines climbing trellises
- use heavy interior window coverings
* Interior
- isolate heat-generating appliances and directly vent that room to the exterior
- replace heat-generating appliances
- replace incandescent with fluorescent lighting
*Roof
- insulate
- lighten the roof color
- plant shade trees
- replace or coat roof with a bright, shiny metal material
- ventilate


You also have "mechanical" ways of cooling buildings. Geothermal cooling, air conditioners, heat exchangers, and solar cooling.

Natural cooling is an ECOnomically Sound approach for your property.

Take a look at this house Phuket South Coast-13 at the bottom of this page :.:. Holmes 4 Homes Phuket

A friend of mine built these houses based on the designs and concepts from the Baan Harn Song Program (energy saving house) program. He had his own website where he went into a lot more detail but I can't find it now. Some research on the Baan Harn Song program may well pay dividends if you're really interested in low impact eco friendly houses.

Originally Posted by dogblower

Take a look at this house Phuket South Coast-13 at the bottom of this page :.:. Holmes 4 Homes Phuket

A friend of mine built these houses based on the designs and concepts from the Baan Harn Song Program (energy saving house) program. He had his own website where he went into a lot more detail but I can't find it now. Some research on the Baan Harn Song program may well pay dividends if you're really interested in low impact eco friendly houses.

Sounds like an interesting project, any idea where plans from the program could be found. Although I don't think you'd be able to keep temps as low as they claim, 4 - 9 degrees lower that the outside temperature.