Sustainable dwelling

Abstract

A dwelling comprises walls defining an interior living space and each having an exterior-facing insulation layer against an interior-facing concrete layer. The exterior-facing insulation layer is a component of a single-sided concrete form used to form the one or more walls. An alternative energy source provides heat energy into the living space. The walls are operable to store and re-release heat energy into the living space.

Description

FIELD OF THE INVENTION

The present invention relates to environmentally sustainable construction, and more particularly to a sustainable dwelling.

BACKGROUND OF THE INVENTION

Typical North American homes are connected to a power grid through which electricity is distributed to the homes from one or more distant power generating sources. It is typical for 100% of the home's power needs, including air and water heating and condition, lighting, entertainment and so forth to be satisfied by the electricity received from the grid, for which the homeowner pays.

It is known to complement the grid power with power generated by an alternative, or independent, energy source, such as a solar-powered generator, a geothermal pump, a ground-air heat exchanger, and a wind-powered generator, or the like. Typically, such devices are capable of generating only 20-30% of the power needed to operate a typical North American home. As such, even when using such devices, there remains the need to draw power from the grid.

It is also known to employ various techniques for reducing the amount of power being drawn from the grid for use by a typical home. These include using high R-value insulation to reduce the speed of warm air loss, and employing construction techniques that reduce air leaks thereby to reduce the heat energy losses, using energy efficient appliances, and the like.

It is an object of an aspect of the following to provide a sustainable dwelling that not only reduces the rate of warm air loss, but stores heat energy from the air generated by a sustainable energy source.

SUMMARY OF THE INVENTION

According to an aspect, there is provided a dwelling, comprising:

one or more walls defining an interior living space and each having an exterior-facing insulation layer against an interior-facing concrete layer, wherein the exterior-facing insulation layer is a component of a single-sided concrete form used to form the one or more walls; and

an alternative energy source providing heat energy into the living space,

wherein the walls are operable to store and re-release heat energy into the living space.

The dwelling provides previously unrealized advantages because it permits the storage, rather than the loss, of excess heat energy provided into the living space and correspondingly enables the dwelling to re-release heat energy into the space instead of generating additional heat energy on demand. This reduces the overall amount of energy required to heat the dwelling when compared with prior dwelling designs that require the generation of new heat energy at the time it is required. According to certain embodiments, the dwelling as a whole being extremely efficient is able to provide excess energy from one or more alternative energy sources back to a power grid to which it is also connected.

The exterior-facing insulation layer being a component of a single-sided concrete form used to form the one or more walls is advantageous because this layer serves a dual purpose as a form for supporting the poured concrete during construction, and as a dwelling insulator.

What results is a dwelling that is very efficiently constructed and consumes very little power as compared to traditionally constructed dwellings. As a consequence, the dwelling requires far less energy to be comfortable to its occupants. Surprisingly, this in turn reduces or even eliminates reliance on the traditional power grid source of energy, and thereby opens up new possibilities for use of alternative energy sources as primary or sole sources of energy in such dwellings.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments will now be described more fully with reference to the accompanying drawings in which:

FIG. 1 is a conceptual drawing of part of a sustainable dwelling.

DETAILED DESCRIPTION OF THE EMBODIMENTS

With reference to FIG. 1, part of a sustainable dwelling 10 is shown that includes walls 20 that define an interior living space 30. The roof and floor are not shown for simplicity. Each wall 20 has an exterior-facing insulation layer 22 made of polystyrene, against an interior-facing concrete layer 24. An alternative energy source 50 provides energy into the living space 30 that is either direct heat, or can be used to generate heat within the dwelling 10. The walls 20 store and re-release heat energy into the living space because of the thermal mass of the concrete layer 24, and heat does not readily escape the concrete layer 24 in the direction of the dwelling exterior due to the presence of insulation layer 22. The exterior-facing insulation layer 22 is a component of a single-sided concrete form, and therefore serves a dual role of being part of the concrete wall construction process as well as an insulator. The single-sided concrete form may include other components such as one or more plywood sheets held in a fixed spaced relationship with the exterior-facing insulation layer 22 during pouring of the concrete by ties.

While not shown in FIG. 1, insulation layer 22 is preferably occluded from view on the exterior of the house by exterior cladding such as aluminum siding, brick or stonework, or wood. Furthermore, doors and windows normally present are not shown in FIG. 1, for the sake of simplicity.

Thermal mass is any material such as concrete that has the capacity to store heat, and is distinct from materials generally classed as insulation such as fiberglass. Materials used for their thermal mass have a high specific heat and density, and while similar to insulation are thus distinguished from insulation by their ability to store heat, as opposed to merely slowing or inhibiting unwanted heat transfer.

It is known generally to employ polystyrene panels as forms during building construction, whereby opposing and space-apart polystyrene panels are held in a fixed spaced relationship creating a repository for pouring the concrete. For example, U.S. patent application Ser. No. 10/997,855 to Victor Amend, the contents of which are incorporated herein by reference in their entirety, discloses various types of insulating forms for constructing concrete walls or floors. Such forms remain in place after the concrete has set, and perform a dual role as polystyrene insulation facing both the interior and the exterior of the living space. Standard heat generating means such as a gas or electric furnace is used for providing heat energy into the living space. However, with such designs the thermal mass of the concrete is not being taken advantage of.

It has been discovered that by creating a sustainable dwelling providing single sided insulated concrete forms—forms that result in concrete walls with an exterior-facing insulation layer and an interior-facing concrete layer—there is a significant and surprising decrease in the requirement for on-demand generation of energy for heating, due to the thermal mass effect. As a result, there is a significant decrease in the power requirements for the dwelling. Thus, a properly constructed dwelling having a living space defined by single sided insulated concrete walls as described above can be heated comfortably with one or more of a solar-powered generator, a geothermal pump, a ground-air heat exchanger, and a wind-powered generator. While each of these heat systems are individually known, they are generally only out of cursory interest employed as supplements to a grid electric power system that employs 100 or 200 amp service to power a gas or oil furnace, or electric baseboard heaters and the like, each of which relies on the grid power. However, with a single-sided insulated concrete wall as described herein, heat energy is far better stored within the dwelling, such that the grid power can become the supplementary source of power whereas the alternative source of power such as a solar power generator becomes the primary source. In some cases, depending upon weather conditions and more particularly the heating requirements of the dwelling, the alternative source of primary power can generate excess energy over a given period that can be directed back to the grid. In this manner, the net power drawn from the grid can in such cases shrink to zero or near-zero over a given time period, so as to in effect provide a so-called “zero energy home”.

In order to further benefit from the energy generated by an alternative energy source such as that described above, one designing and orientating the dwelling may take various additional factors into account. For example, a bulky rectangular or square shaped dwelling, preferably a single storey that minimizes wall surface area can be advantageous. Several large windows facing south and very few facing north (for southern areas do the opposite) takes advantage the disposition of the sun to either heat or shield from excess heating of the house. The passive heat gain from incident sun can provide 40% of needed heat energy. Furthermore, by minimizing the number of external doors, the volume of air leaks are reduced. Airtight construction is facilitated by ensuring that all windows and doors meet the required air-leakage standards, and by ensuring the vapor barrier (where needed) overlaps by 500 mm at the seams and is and sealed everywhere. Triple glazed windows and well insulated or double external doors reduce the loss of heat energy also, as does the use of a limited number, or no, skylights. Cold bridges are avoided by installing insulation without any penetrations, and running ducting in heating/conditioning spaces only.

The use of energy efficient appliances and low energy goes a long way to reducing the required power consumption.

The use of radiant floor heating offers many advantages over traditional heating systems. The most important advantage is the improved comfort level, especially when combined with a concrete floor. Radiant heating allows a room to be heated evenly by increasing the room's average surface temperature. Another key benefit of radiant heat is energy efficiency, due to being able to achieve comfort at lower air temperatures.

Tankless water heaters are useful because they provide water heating on demand, as opposed to the inefficiencies inherent in having to maintain high temperature of water in a tank at all times.

With the various construction techniques described above, it has been discovered that energy requirements can be reduced by approximately 70-80%. At this level of reduction in energy requirements, the use of a renewable source of energy can easily supply the remaining 20-30% of energy.

It will be understood that, although embodiments have been described that do not require power from the electrical grid, other embodiments of the sustainable dwelling will receive and send power to and from the grid, resulting in a zero or near-zero grid power requirements. Still other embodiments of the sustainable dwelling will receive a very small amount of power from the grid on an ongoing basis, but benefit from the drastic improvements in energy efficiency provided by the combination of the wall construction and alternative energy source as described above.

It will also be understood that embodiments may include single sided insulated concrete floors or ceilings that also store heat energy.

Although embodiments have been described, those of skill in the art will appreciate that variations and modifications may be made without departing from the spirit and scope thereof as defined by the appended claims.

Claims

1-13. (canceled)

14. A method of providing a dwelling, comprising:

creating a single-sided insulated concrete wall form by holding one or more sheets in a fixed spaced relationship with an exterior-facing insulation layer;

pouring concrete into the wall form as a concrete layer thereby to form at least one dwelling wall defining an interior living space, the concrete layer facing the interior living space; and

coupling an alternative energy source to the living space thereby to provide heating or cooling energy into the living space.

15. The method of claim 14, wherein the creating comprises holding the one or more sheets in a fixed spaced relationship with the exterior-facing insulation layer using ties.

16. The method of claim 14, wherein the sheets are plywood sheets.

17. The method of claim I 4, further comprising diverting excess energy from the alternative energy source to an electrical power grid.

18. The method of claim 14, wherein the altemative energy source comprises a solar-powered generator.

19. The method of claim 14, wherein the alternative energy source comprises a geothermal pump.

20. The method of claim 14, wherein the alternative energy source comprises a ground-air heat exchanger.

21. The method of claim 14, wherein the alternative energy source comprises a wind-powered generator.

22. The method of claim 14, further comprising providing an energy efficient appliance.

23. The method of claim 14, further comprising providing a tankless water heater.

24. The method of claim 14, further comprising providing a radiant floor heater.

25. The dwelling of claim 14, wherein the insulation layer is made of expanded polystyrene.