guide to energy efficient homes

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Guide to Energy Efficient HomesGuide to Energy Efficient Homes

Steps to make your home energy efficient


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Guide to Energy Efficient Homes

Energy Efficient Homes

nergy Efficient Homes refer to homes designed in such a manner which

facilitate optimum and efficient usage of resources, mainly energy,

water and material. They are less harmful for the environment and

contribute minimally to environmental pollution. These buildings are sometimes

called Green Buildings. Energy efficient homes cost much less to heat, cool and

light, compared to a typical home.

E

Achieving energy efficiency for homes is a step towards the goal of zero-carbon

homes. A zero carbon home uses less energy than it generates over a set

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period of time. A carbon footprint is calculated for the full life of the home,

including the CO2 emissions created during the build of a house and its day-to-

day energy needs. This figure is then offset by the propertys ability to produce

the energy it needs itself through wind turbines, solar panels and other

renewable sources of energy all important elements that have been purpose-

built into the home in the design.

If a property is able to become fully sustainable, and even have excess

renewable energy supplies that can benefit others, then it has fully become a

zero-carbon home. Part of the key to going zero carbon in the home is an

awareness of how to make the property itself more energy efficient and finding

ways to reduce our everyday energy needs.

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Meaning Of Energy Efficiency For Homes

While the whole world seem to be divided on the issue of global warming, its

effects continue to become much more evident. Submerging coastal lowlands,

sinking islands, melting polar ice the list of effects of global warming is quite

lengthy. Global warming is one of the most serious environmental issues

threatening the very existence of various plants and animal species on the

planet. Over the last 100 years, the global near-surface temperatures has

increased by 0.32F as a result of various natural as well as anthropogenic

causes of global warming. That being said, one also needs to take into

consideration that the natural causes of global warming play a crucial role in

stabilizing the temperature of the planet - and without them Earth would have

been freezing cold and unsuitable for human habitation. More importantly, global

warming statistics also reveal that the rate at which it is occurring has increased

manifolds over the last few years, and if the same trends continue we will

experience a rise of 2.0 to 11.5F on the planet by the end of this century.

When we talk about the effects and consequences of global warming on the

environment, we refer to its effects on various attributes of environment - which

includes flora, fauna and humans. Basically, these effects of global warming on

various life forms on the planet are attributed to climate change triggered by

incessantly increasing global near-surface temperatures. The most prominent

global warming effects on weather include extreme weather conditions - such as

frequent droughts, heat waves, devastating hurricanes etc., all of which in turn

affect various life forms on the planet. Given below are the details of global

warming effects on planet Earth - with special emphasis on its effects on plants,

animals and humans.

Governments across the world are debating on the effects of global warming and

ways to arrest the process before it is too late. Over the past few decades, the

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debates on global warming have gained momentum and organizations and

governments have come up with various solutions to reduce global warming and

its impact. First of all, people should understand the problem and take measures

accordingly to save the world.

One such approach is the movement towards making homes energy efficient

where by homes do not depend on public utility for their energy needs and at the

same time do not emit carbon dioxide (by reducing use of fossil fuel). People

should reduce the usage of electrical appliances which emits green house gases.

For example, the refrigerator releases chlorofluorocarbon (CFC) and the

incandescent light lamp emits 300 pounds of carbon dioxide a year. This can be

replaced by a compact fluorescent light bulb which saves much energy. Usage

of green power prevents 300 kg of carbon dioxide to be emitted into the

atmosphere. The electricity obtained from the renewable resources like wind and

water is called green power. The cost is also low in case of green power.

Insulation of the ceiling of a house and power saving is the important factor to

reduce global warming. The electric appliances should be switched off instead to

hold it in stand by mode. This will save more power since stand by mode

consumes 40% of the energy.

In short, making our homes energy efficient is a step towards controlling global

warming and its effects. How do we achieve energy efficiency at our homes?

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Ways To Achieve Energy Efficiency

Here are some of the steps you can take to achieve energy efficiency at your

home. They are all ways to save energy for your homes. Some of them are

habits that cost you nothing except being conscious about being energy efficient.

Some of them require slight lifestyle changes without causing you much

discomfort. Some of the steps require you to install equipments to tap into

renewable sources of energy and require some investment, but the investments

will prove to be worth given the benefits in the long run.

Energy Efficient Habits and Other Tips

1. Turn off lights youre not using. You may not notice when an unwanted light

is on, especially during the day, but they are wasting power every hour

without any benefit to you. So, turn them off and save that energy.

2. Schedule an energy audit. Your local utility will probably provide an audit for

free, and you may also get a more comprehensive audit (saving you more

money in the long term) by paying for a whole-house audit. (Up to 50%

energy savings per year).

3. Do not heat or cool empty rooms. If there is a room in your house that is

rarely used, close off the vents to save on heating and cooling.

4. Turn off your electronics. If youre going to be away from your computer or

other appliance for more than an hour, turn it off, and you will save about 5%

energy per year.

5. Eliminate phantom load. Televisions, stereos and computers draw a small

but steady amount of phantom power even when turned off. Together, they

can suck up the equivalent of a 100-watt light bulb running round-the-clock.

Put them on surge-protecting power bars, and turn off the bar when not using

the appliances. You will save about 5% energy per year.

6. Make your fridge more efficient. Keep your refrigerators coils clean to boost

its overall power, and store jugs of water in any empty space inside, because

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storage), it is our collective peak demand that triggers the building of more

polluting power plants.

3. Wash clothes in cold water. Your clothes will get just as clean on half the

energy. This will save you 7% energy per year and a pile of money in the

process over years.

4. Give up your dryer. Hang your clothes to dry on a clothesline or indoor rack

with no additional use of energy to dry your clothes, and that saves you 10%

energy per year.

5. Reduce your water use. Simple ways to save water include fixing any leaks

and replacing faucets and showerheads with low-flow options, and you save

3% energy per year.

6. Install ceiling fans. Reduce your air conditioner usage with ceiling fans. Look

for Energy Star models that use 50 percent less energy. Using ceiling fans

instead of air conditioners, you save 19% energy per year.

Purchasing Decisions Toward Energy Efficiency

1. Buy energy-efficient compact fluorescent bulbs for your most-used lights.

Although they cost more initially, they save money in the long run by using

only 1/4 the energy of an ordinary incandescent bulb and lasting 8-12 times

longer. They provide an equivalent amount of bright, attractive light. Only

10% of the energy consumed by a normal light bulb generates light. The rest

just makes the bulb hot. If every household in our country replaced one of its

standard light bulbs with an energy efficient compact fluorescent bulb, we

would save the same amount of energy as a large nuclear power plant

produces in one year. In a typical home, one compact fluorescent bulb can

save 260 pounds of CO2 per year.

2. Upgrade your appliances. Look for the Energy Star, and you may be eligible

for a tax break and obviously a 3 12% energy savings per year.

3. Dont waste energy on TV. With the switch to digital TV coming, many people

are buying new, digital-ready TVs. If you must shop for a new television, look

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for an LCD (liquid crystal display) screen, which uses six times less energy

than a plasma screen (2% energy savings per year).

4. Get a programmable thermostat. Automate when your heating or cooling

systems come on to save energy while you sleep or are away from home.

This will save you about 10% energy per year.

5. Replace your windows. Above in this section, there was a recommendation

for working with the windows you have. Replacing your windows with more

energy-efficient versions can save you even more (14% energy savings per

year).

6. Upgrade your hot water heater. Save energy and space by upgrading to a

tankless or solar hot water heater. They save you 14% energy per year.

7. Use less hot water by installing low-flow shower heads. They cost just $10 to

$20 each, deliver an invigorating shower, and save 300 pounds of CO2 per

year for electrically heated water, or 80 pounds for gas-heated water.

Plugging into Renewable Energy Sources

Renewable energy is usually considered a break from non-renewable fossil fuels

and oil to a renewable, cleaner system of producing energy. Fossil fuels will run

out at some point. We can't get them back - once they're gone, they're gone. A

major benefit to researching and using alternative energy options is that we

waste less of the fossil fuels we actually have left, and protect our ability to

eventually maintain energy in spite of few or no non-renewable energy sources.

The biggest benefit to using alternative energy is that it's a cleaner, safer option

for both people and the planet. Global warming is the result of overuse of oil and

fossil fuels which don't burn clean and in fact create massive pollution issues.

Right now of course we have oil and other non-renewable energy available, but

that doesn't mean you shouldn't quit using it in trade for cleaner alternative

sources. Besides being better for the planet, alternative energy can provide you

with an energy efficient house and save you money in the long run. It also means

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that you aren't dependent on the energy grid or electric company. Say there's a

black out due to weather, while everyone else in the neighborhood is out of

power, a home powered by solar or wind may still be up and running.

Following are some sources of alternative energy.

Solar Generated Energy: Solar energy is not as unreachable as many may

think. You don't have to live in the hot sunny desert to utilize solar. Solar power is

actually something most people across the globe can use, even if you live in an

often cloudy and rainy area or a place with extra cloudy winters.

By the simplest definition, solar

systems work by absorbing

sunlight and converting it into

energy - such as heat, hot

water, and light. Of course solar

systems vary wildly but all are

more earth-friendly then using

oil or gas for energy. The best

solar systems combine passive

solar techniques with other active solar technology such as photovoltaic.

Benefits of solar energy include:

Clean energy source that is ultimately renewable and will not harm the

planet in any significant ways.

Solar has become mainstream enough that it is not expensive to build a

solar home or to remodel your existing home for solar.

The same techniques that work to heat your home with a passive solar

system also work to cool your home. When done correctly, passive solar

provides a comfortable home year round.

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Wind Generated Energy: Like the sun,

wind can also be used to generate clean,

renewable energy. Wind thus far is not

as predictable as solar power and cannot

be used in quite as many places solo.

However, when paired with a solar

system, wind is a great compliment

system such as when the cloud blocks

the sun, wind tends to pick up.

Some countries have used wind power for some time with success and wind has

recently gained massive popularity in the U.S., becoming one of fastest growing

alternative energy option around. Like solar, there are plenty of wind systems

available. Researching the best wind power option for your particular site and

home is very important. Not all systems works as well for all areas. This is one of

those times you may want to meet with a renewable energy consultant.

The good news is that wind power options are becoming easier to self install.

You can even set up your own home made wind turbine.

Heating and Cooling with Solar Energy

A major part of our energy requirements is for keeping our homes warm during

winter and cool during summer. It is good news that we can utilize solar energy

to cool or warm our homes passively without depending on the utility power

supply and without burning fossil fuel.

Passive Heating Using Solar Energy: Passive heating techniques can be used

to reduce, and in some cases eliminate, mechanical air conditioning

requirements in areas where heating is a dominant problem. The cost and

energy effectiveness of these options are both worth considering by homeowner

and builders.

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Passive solar heating in particular makes use of the building components to

collect, store, and distribute solar heat gains to reduce the demand for space

heating. It does not require the use of mechanical equipment because the heat

flow is by natural means (radiation, convection, and conductance) and the

thermal storage is in the structure itself. Also, passive solar heating strategies

provide opportunities for daylighting and views to the outdoor through well-

positioned windows.

It is best to incorporate passive solar heating into a building during the initial

design. The whole building approach evaluates it in the context of building

envelope design (particularly for windows), daylighting, and heating and cooling

systems. Window design, especially glazing choices, is a critical factor for

determining the effectiveness of passive solar heating. Passive solar systems do

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not have a high initial cost or long-term payback period, both of which are

common with many active solar heating systems.

In heating climates, large south-facing windows are used, as these have the

most exposure to the sun in all seasons. Although passive solar heating systems

do not require mechanical equipment for operation, this does not mean that fans

or blowers may not, or should not, be used to assist the natural flow of thermal

energy. The passive systems assisted by mechanical devices are referred to as

"hybrid" heating systems.

Passive solar systems utilize basic concepts incorporated into the architectural

design of the building. They usually consist of: buildings with rectangular floor

plans, elongated on an east-west axis; a glazed south-facing wall; a thermal

storage media exposed to the solar radiation which penetrates the south-facing

glazing; overhangs or other shading devices which sufficiently shade the south-

facing glazing from the summer sun; and windows on the east and west walls,

and preferably none on the north walls.

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Passive Cooling Using Solar

Energy: For optimum summer

cooling, a building's

surroundings should be

designed to minimize summer

sunlight striking external

surfaces, and to prevent

surrounding area heat re-

radiation and reflection. Great

temperature differentials

between desert exterior conditions of 110+ degrees and 78 degrees required for

interior comfort can be tempered using "thermal decompression" zones that

become increasingly more effective as one nears the building. Mitigation of

undesirable summer direct sun and thermal impacts is achieved through use of

vegetation i.e. deciduous trees which interrupt the summer sun's direct path, and

ground covers which prevent ground reflection as well as keep the earth's

surface cooler thereby preventing re-radiation. One moves out of intense direct

sun and heat through vegetation that filters sunlight and shades the ground; then

through a more densely filtered zone with ground covers; then through a patio

area with vegetation, trellises and water features; into a tempered building entry

("thermal lock"); and finally into the building proper. This movement, 110 degrees

stepping down in stages to 78 degrees, allows the body to adjust properly, and

provides the best means of arriving at a lesser differentiation between the

building's perimeter wall interior and exterior surface temperatures. It is this

difference, between interior and exterior surface temperature, that exacerbates

the amount and rate of heat flow through the material. Glazing should be

minimized on the roof and the east and west walls where summer sunlight is

most intense.

Intense direct solar impacts from the sun rising in the east are equal to those of

the setting west sun. The reason we feel the setting sun impact more is due to

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the added thermal impact of the earth reradiating the heat it has gained during

the day. The summer sun is much higher in the sky and has a negative impact on

skylights and roof windows and lead to enormous solar heat gains. They should

not be used in hot climates unless they are insulated and/or shaded. Vertical

south facing glass (windows, clerestories, etc.) with overhangs or shades,

present fewer problems but are still adversely affected by exterior air

temperature. A horizontal overhang or an awning above a south window is an

inexpensive, effective solution. If it protrudes to half the window height (Fig. 21),

such an overhang will shade the window completely from early May to mid-

August, yet allow for winter sun access. A trellis with deciduous vines can be

used. Another good strategy is the use of deciduous trees that shade the south

face and roof during the summer. All these shading methods work equally well

with Trombe walls, water walls, greenhouses, and other south-wall passive solar

collector strategies.

Shown below are two models of passive solar cooling for homes. One technique

uses prevailing winds to bring earth-cooled air into living areas. Passive solar

gain is used to heat solar chimney vent surfaces, drawing hot air up and out of

the house. The one on the right is hybrid cooling that uses coolth tubes run

through foundations to cool and recirculate interior air with photovoltaic powered

fans.

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Pros and Cons of living in a Green House

There are many advantages of living in a Green House as well as manydisadvantages. Here are some of the advantages:

Green house living reduces the dependency on non-renewable fuel

sources. As the home owner is responsible for generating the energy for

the family's needs, more attention is likely to be given to energy saving

devices and changes in lifestyle that will reduce the amount of energy

consumed and make the home more energy efficient. Generating energy

from renewable sources can work out as a very economical option over

time.

While there may be substantial start up costs, the running costs can be

minimal compared with traditional energy supply costs.

There are often large support networks that are available to green living

home owners. This can help to build a community with like-minded ideas

and common goals.

Some of the disadvantages include:

The site of a home that is suitable for off the grid living is important. If

energy is to be derived from sun, wind or hydro sources, then there must

be good access to these resources. A home that is going to be powered

by solar energy, for instance, must be able to site the panels in a place

that is not shaded.

There can be significant start up costs that a home owner will have to

face. Some off grid homes are built as self-sustaining communities and

this helps to overcome the cost issues.

There are often planning issues which may make it difficult for an off the

grid house to be built in an urban area.

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There may be life style changes that need to be adopted in order to

conform to green-living principles. Changing habits and life styles may be

a tough task for some people.

The main sources of alternative energy, namely solar energy and wind energy

have their own pros and cons too. Let us examine them.

Pros and Cons of Solar Energy

In a world where fossil fuel has become a four-letter world, turning to alternative

energy sources is no longer simply a desire to be more environmentally friendly;

it's a growing necessity in order to no longer be dependent upon foreign oil and

reduce emissions.

One of the biggest breakthroughs in solar energy came five years ago and is

anticipated to be on the market some time in 2011. Spray on solar power cells

actually harnesses 30 percent of the sun's rays by capturing infrared rays,

whereas conventional solar power only captures up to six percent, non-infrared.

This nanotechnology will change the face of solar energy as you know it.

Although this product is yet to be on the market, it is an example of the progress

being made in alternative energy

Pros of Solar Energy

The biggest pro for solar energy is the fact that the sun and the energy it radiates

are free. Additional advantages include:

1. The uncertainty of home fuel oil prices and the constant fluctuation in

pricing makes the general public vulnerable and at the mercy of high oil

prices.

2. The negative environmental impact that's the result of drilling for oil and

the end result of burning fuel oil makes solar power a very attractive

alternative. With solar power, you know what your cost is up front - the

purchase and installation of your solar unit. Other than the need to buy

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replacement batteries every ten or fifteen years, you won't incur constant

energy expenses.

3. Sell back revenue is possible with solar energy. One of the best

advantages to using solar energy to power your home is that you can sell

any excess energy back to the power company. This can be a factor in

off-setting your initial investment.

4. Solar energy is one of the best clean, renewable and sustainable energy

sources.

5. Tax credits are available from both federal and state at the present time.

Some municipalities also give special tax breaks to alternative energy

systems.

6. The green initiative to push the green industry forward is helping to

advance solar power to be far more efficient than the first photovoltaics

used to produce energy a decade ago.

7. Some contractors are building homes with solar and other alternative

energy systems and include the cost in the overall purchase price of the

homes, eliminating the upfront cost of installation in new construction.

Most of these homes are also available for tax credits.

8. First Solar is the first manufacturer of thin film PV (Photovoltaic) modules

and is revolutionizing the solar power industry. This application has also

been tested on solar airplane, the first of its kind.

9. Another new technology allows solar cells and panels to collect enough

energy to power your home even on cloudy days. This is a major break

through that came about over the past couple of years and is helping to

reshape the solar industry application. You no longer have to live in a

sunny area to benefit from solar energy.

10. Several companies now operate a lease and lease-to-own solar

programs. Some power companies are also offering these programs to

customers. Your lease is set at a fixed rate that won't change and the

monthly cost is the equivalent of a normal month's power bill.

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11. Gone are those ugly large panels. You can now purchase attractive solar

roof tiles. If you have clay styled tiles on your roof, you can replace them

with solar designed tiles that look like the real thing.

Cons of Solar Energy

If you're going to consider solar energy as your power source, then you must also

review the cons in order to assess which column, the pros or the cons, outweighs

the other. In the past, the return for your investment was greatly disproportionate

to your return. While the investment is still large, the time span that you can

actualize a return has become more economical in many cases.

1. Cost: The initial outlay of cash is a big investment. This is true for the

majority of the systems. If you can locate a company in your area that

leases solar equipment, then you can get started immediately without a

large investment. Unfortunately, there aren't too many companies offering

this option and the majority that do are located in the western part of the

US for obvious solar application reasons. You need to explore all of your

options before committing to a system. Get referrals and also see if your

local utility company offers any assistance a leasing program or a lease-

to-own option.

2. Location: You need to live in a sunny location to rely on solar energy. This

is a necessity with the majority of systems currently on the market;

however, there are a few companies that claim to have developed cloudy-

day friendly solar panels. With new technology being brought out onto the

market, you need to stay on top of the latest developments that becoming

available to consumers.

Once you're armed with facts and have spent time researching companies and

the differences in their products, you can be confident in whatever decision you

make concerning the pros and cons of solar energy for your home will be the

right one for you and your family.

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Pros and Cons of Wind Energy

Pros of Wind Energy

Here are some of the ways in which wind energy proves beneficial to us.

The biggest benefit one can reap out of wind energy is that it generateselectricity, but does not release any harmful pollutants or gases as by

products. This therefore makes it a safer and cleaner source of energy.

Wind energy is also one of the cheapest forms of energy available today

and therefore it can be used by everyone, including poor farmers from

rural areas.

Farmers can not only use the electricity for themselves, but can also earn

income out of it, by providing electricity to several homes.

Wind energy does not involve the use of any fossil fuels or non-renewable

sources of energy like natural gas, coal or oil. This proves that it is an

efficient renewable energy.

Wind is a never ending resource, therefore power cuts and power failures

are almost non-existent in areas that rely upon wind power to generate

electricity.

With the use of larger electric grids, higher amount of electricity can be

generated, which thus makes electricity accessible to a larger number of

households in the vicinity.

Cons of Wind Energy

Let us now look at the flip side of the coin. Wind energy does have some

shortcomings. Find out what are those.

Wind turbines can get damaged or completely destroyed when hit by a

heavy storm or a severe lightning.

Wind energy helps to solve the electricity problems up to a large extent,

but it does not eliminate it completely. It therefore signifies that, we still

need to come up with other better options.

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Wind does not necessarily flow in the same speed all the time. Therefore,

the production of electricity would not always remain consistent, there

might be ups and downs in its production, depending upon the speed of

the wind. This inconsistency in electricity production affects its supply in

the nearby high demand areas like cities and towns

There have been instances in the past, when the rotating blades of the

turbines have proved fatal for birds that happened to hit it.

Wind turbines, on an average make a sound of about 50-60 decibel.

Slower the wind's speed, larger is the sound produced.

In recent times, some people have claimed that wind turbines lower the

aesthetic beauty of the land! However, I think that, it is a matter of

individual perception and not everyone looks at things in the same way.

Wind energy will forever remain a 'near to perfect' source of energy for us, yet

due to its disadvantages, the conquest of finding out a perfect alternative

continues. So let us hope for its emergence in the near future and handover a

better planet to our future generations.

Energy efficient housing is a great aspiration. Even if it is not feasible to goentirely 'off grid' there are many ways that homes can decrease their dependency

on the main energy supplies. Every step towards greener living, however small,

has far reaching positive effects.

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guide to energy efficient homes

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