FAQs

The following are a list of common questions about energy efficient housing.

What is a Zero Energy Home?
What is net metering?
How do you make a house 'Zero Energy'?
What is fluid modeling?
What is energy modeling?
What kind of energy efficient changes do you recommend?
People won’t pay extra for a green or energy efficient home, right?
What rebates are available for energy efficient installations?
How many solar panels will the house need?
What can you do to hide the solar panels?
Will the homes still work when it’s cloudy?
What happens if some aspect of the solar power system is malfunctioning?
What happens when the grid power goes out? Will there still be power in the house?
Can a solar system have backup battery storage?
Can you design a house to be completely off the grid?
Is there a need to periodically clean solar panels or sweep snow off of them?
What is a solar thermal system?
What is ground source heat exchange (geothermal)?

A Zero Energy Home produces as much energy as it consumes over the course of a year using renewable resources.

Net metering is the process of measuring both the amount of energy you draw from the grid and the amount of energy you put back into the grid. This is accomplished through your electric meter’s capacity to spin in both directions, and through the use of renewable sources to generate that energy.

Designing a home to be Zero Energy is a complicated process but includes two basic tenets. First, use all possible passive solar design techniques to reduce the energy requirements of the home. Second, use the appropriate amount of renewable energy to supply the home’s remaining energy requirements.

In meeting these two very basic principles, the design of a Zero Energy Home considers many factors, all of which work together as a highly-efficient system. Examples of these factors include: proper orientation of the house on the lot, decades of historical local weather data, use of passive solar techniques, selection of the appropriate construction method, use of airflow and energy modeling software, selection of better building materials such as triple-glazed windows and more insulation, tightening of the building envelope, selection of an efficient lighting and appliances scheme, proper sizing of heating, air conditioning, and ventilation systems, and inclusion of renewable energy sources like solar electric and solar hot water.

Fluid modeling is used to test internal airflow and ventilation patterns, predict air quality over the seasons, and analyze temperature fluctuations over time throughout a home.

Energy modeling uses software programs, up to 30 years of local weather data, and solar path predictions to project a building’s monthly and annual energy use. Energy modeling is used to quantify and asses the effect a given home improvement will have on the overall energy usage of a home.

Recommended changes can vary widely including HVAC sizing issues, day lighting schemes, basic insulation choices, home orientation, appliance specifications, glazing placement, techniques to tighten the building envelope, etc.

When surveyed directly, more than 50% of builders claim that buyers are willing to pay more for green building elements. Small builders reinforce this notion at 61% and larger builders at 49%. (McGraw-Hill Construction, 2006)

There are federal, state, local, utility based, and manufacturer related rebates and tax credits, which change over time and according to state. There are links on our website that can bring you to your locality or utility so you can see which of these financial incentives may be available where you live.

The number of solar panels is proportional to the amount of energy required by the home’s systems, which is dependant primarily on specific location/climate and the usage patterns of the inhabitants. You should consult a solar engineer to size a system appropriate to these needs.

There are a number of ways to make solar panels less visually obtrusive. These include designing the roof to accommodate the panels from the beginning, choosing a dark roof color similar to the panel color, installing the panels nearly flat on the roof, making sure the panels are aligned with the roof pitch, mounting them on the back of the roof and away from the street, mounting them on the garage instead of the house, and mounting them on a pole or ground mount away from the house. In some climates, solar panels can be used that actually appear to be roofing material.

Yes. But it is recommended that most homes be grid-connected so that your home can draw electricity from the grid when it is unable to pull energy from the solar panels. Conversely, on sunny days, when you generate more power than you use, grid-connectivity allows you to sell that excess power back to the utility company, effectively spinning your meter backwards. Being grid-connected also eliminates the need to use batteries.

Most manufacturers warranty their solar panels for 25 years. Your solar installer should be able to perform any necessary servicing, or should be able to contract for those services. Because the house will likely be grid-connected, you will not lose power should any malfunctions occur. Note, however, that the solar panels themselves are very durable and have no moving parts. Depending on your roofing materials, they will likely outlive the roofs they are installed on.

During daylight hours, you will have power; however, nighttime power will be available only if an additional power system is installed, such as a battery back up or a generator.

Yes, backup systems can be designed with storage batteries that can keep the house going for several hours or several days if you so desire.

Yes, off grid homes obviously don’t have access to outside power, so they generally require more active energy systems as well as substantial backup storage. An off-grid home will be considerably more expensive than a zero net energy home.

Solar panels handle snowy climates quite well. Because solar panels are typically installed at an angle and the surface of a panel is smooth glass, snow slides off of them in the same fashion as snow slides off of a metal roof. In addition, the dark color and inherent heat absorption, aid the self-clearing by melting any accumulated snow.

A solar thermal system is a closed system that uses the sun’s energy to heat water for your home. Generally speaking the solar thermal system uses a liquid which feeds into a tank which in turns heats the water. The liquid in the system never touches the water that reaches your tap.

Ground source heat exchange is a system of pipes or wells that run either vertically or horizontally in the ground. They take advantage of the fact that the earth, several feet under the surface is generally about 54 or 55 degrees all year round. By running pipes into the ground, the water inside them is heated or cooled to 54 or 55 degrees. This means that if the ambient air temperature in winter, there’s roughly 25 degrees of heating that can be drawn from the earth. And if the ambient air temperature in summer is 80 degrees, that gives you 25 degrees of available cooling. The water pipes run through a heat pump which is electrically powered. Because the pumps use electricity, they are not considered a renewable energy source per se and generally do not qualify for tax credits or rebates. However, the systems are generally extremely efficient, and if your electrical needs are being provided by PV, then power the ground source heat exchange system is essentially free.

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