Here Comes the Sun: Are Solar Panels or Passive Solar Design Right for Your New Home?

When James Tozza and his family installed PV panels on their home in April, they were the first in their Saugus, Mass., neighborhood to go the solar route. “Now we have three different neighbors with PV panels — we sort of started a trend in the area,” says James Tozza.

The Tozzas opted for a no-money-down solar leasing program from Vivint Solar and haven’t looked back. The process was quite simple: “Installation only took a few days and we don’t have to do any upkeep ourselves,” Tozza says. “We didn’t pay anything up front and now pay Vivint a monthly fee that is much smaller than our old electric bill.”

The Tozza family is just one example of the growing number of ordinary families choosing to install solar panels on their home. From solar-powered garden lights to sprawling solar farms to innovative solar panel design, there’s a solar energy option for almost everyone.

Photovoltaic Panels 101

What’s the magic that allows you to harness the power of the sun? Solar panels are photovoltaic — they convert solar radiation into direct current electricity in order to generate electrical power using photovoltaic semiconductors that absorb the photons in sunlight. Panels are made up of multiple cells that are connected electrically and usually contain a top protective layer, two layers of treated silicon, collecting circuitry and a layer of polymer backing. Panels are combined to form an array, which consists of one (or more) batteries, a controller (for stand-alone systems), an inverter (for grid-connected systems) and wiring and framework.

Scientists first developed PV cells to power orbiting satellites and other spacecraft, but today’s PV converters are widely used for grid-connected power generation. Solar voltaic cells can generate electricity from both direct and indirect sunlight, so your solar panels still function even on cloudy days. Even rain helps, washing away dirt to keep the panels clean.

What Are Your Options?

Installing solar panels on your home doesn’t have to be an enormous undertaking — solar energy systems are gaining popularity as technological advances and leasing programs change a once cost-prohibitive industry.

When designing your new home, consider whether installing solar panels or implementing a passive solar design might be right for your family (see part two of this series, on passive solar design below). Not only can solar energy save up to 50 percent of energy costs, but it can increase the resale value of your home. Luckily, a variety of options exist to help you begin the transition to solar energy. For the commit-a-phobes, options include cheap garden lights (around $3) or solar-powered battery chargers for your laptop and/or cellphone.

If you want to seamlessly integrate solar power in your new home, it’s best to plan for and install during construction. Doing so will allow you to achieve the optimal orientation for your PV panels while incorporating them into your home’s design. “In the past, PV systems were a clunky afterthought added on top of the homes of early PV adopters,” says John Prater, vice president of Operations at HelioVolt in Austin, Texas. “Now, we are working with a number of homebuilders to develop systems which integrate seamlessly into the home design — they add to the aesthetics of the home while enabling the homeowner to independently manage down their electricity expenses.”

If you’re the do-it-yourself type, solar energy kits are available that allow for relatively easy installation. One benefit of newer kits is the use of micro-inverter technology, in which each PV panel has a proprietary inverter mounted right by the panel, making the kit easier to install. Federal tax credits and state rebate programs can help with high initial cost of PV panel installation, but rapidly falling prices may eliminate the need for future incentives.

Companies such as Vivint Solar have come up with alternatives to make solar energy affordable for the average buyer — solar leasing programs allow homeowners to install solar panels for no money down, while incentives and tax breaks are passed on to the installation company. In the program, a solar energy company pays for the up-front installation costs, while the homeowner pays the company a long-term monthly leasing rate that’s about 10 percent lower than their average utility bill.

“Prices for solar panels have dropped dramatically in recent years,” says Danielle Murray, LEED AP and Renewable Energy Program Manager at the San Francisco Department of the Environment. New financing options allow homeowners to install solar with little or no money down, with monthly payments structured to be more than offset by savings on their utility bill.” Banks, large corporations and even crowd funding help finance leasing efforts. “Almost all of the costs of solar are accounted for in ‘initial’ costs; once installed, a PV system is warranted to produce electricity for 25 years,” says Prater. “Such an ability to produce electricity without additional fuel charges is one of the qualities that makes solar so desirable and such a great investment.”

Looking Forward to a Bright Future

An efficient way to store solar energy isn’t available yet — batteries are too expensive and don’t last long enough to pay for themselves, so there will be times when your solar panels are producing more energy than your household needs. “In the near future, I believe you will see even greater innovation that integrates solar energy, energy storage and home automation that will serve to ‘shape’ energy use to lower the overall utility bill, while also providing a secure supply of power during emergency outages,” Prater says.

If your PV panels are connected to the grid, many states offer a net-metering program that allows consumers to receive credit for the solar energy they produce when they’re not using it. For example, when everyone is out of the house during the day at work or school, your solar energy system is working hard from home and receives credit for producing a surplus of energy. This credit is put toward the energy you draw back from the grid at night, on cloudy days or any other time where you use more energy than the panels can produce.

Because solar energy is so dependent on the weather, it’s not the best energy saving option for every climate, says Jeffery P. Tamburro, certified RESENT Energy Rater in Denver, Colo. “I don’t think solar, or any other forms of renewable energy for that matter, will ever eliminate the need for fossil fuels, but it will enable us to stretch those fossil fuel supplies well into the future.”

A home using solar energy in sunny Phoenix, Ariz., will save up to 50 percent on its electricity costs, while a similar home in rainy Seattle will not experience the same savings. Keep in mind that solar energy is usually a supplement — it isn’t designed to offset 100 percent of your regular on-the-grid electricity.

Regardless, solar energy has a bright future. Innovations originally developed for military use, such as moveable/roll-up panels and cells in windows are being adapted for the public. Developers are considering solar roof shingles and other advances to make the technology even more efficient and affordable, as well as increase its curb appeal. HelioVolt’s thin-film Copper Indium Gallium Selenide (CIGS) panels provide a new look for homeowners who don’t like the “patchwork quilt” design of traditional PV panels — and are better able to create energy using off-angle or low light.

Harvesting solar energy through PV panels is an increasingly popular option for those environmentally conscious homeowners wanting to save on energy bills. While PV panels do not make sense in every home, it’s certainly worth considering your energy needs to see if installing a system might lower your utility costs.

“In our passive solar house, we only turn on the air conditioner two weeks out of the year,” says Joseph Pro, a New York City-based architect with more than 20 years of experience in passive solar home design.

Passive solar is a great option for environmentally conscious buyers, Pro says. “With the proper orientation, insulation and windows, as well as a commitment to passive solar, you can greatly diminish or even eliminate your energy consumption.”

What’s the Benefit?

If you choose a passive solar design for your new house, count on it improving your home’s natural light and organically regulating its indoor temperature — while reducing your electric bill and impact on the environment.

At its core, passive solar design elements use sunlight to naturally ventilate, warm, cool and light your home’s interior. Your home’s orientation is essential to taking advantage of sunlight: toward the south in the northern hemisphere or toward the north in the southern hemisphere.

“Siting the house is one of the most important elements to passive solar design. About 60 percent of houses have the wrong orientation — the garage is usually southern-facing and absorbs the most heat from the sun,” Pro says. “We get tons of requests from homeowners to change the garage into the living room to take advantage of the sun.”

Passive Solar Design Has 5 Key Elements

With the proper orientation, a passive solar home relies on five elements to regulate its climate. The first element, the aperture, is the opening (often a window) through which heat and sunlight enter the space. An ideal aperture is within 30 degrees of true south and receives unobstructed sunlight from 9 a.m. to 3 p.m.

Once sunlight passes through your southern-facing windows, it must hit the absorber. The second element of passive design, the absorber is the dark, hardened surface of the storage element, which sits in the direct path of the sunlight. The absorber is typically a masonry wall, floor, partition or water container that initially absorbs the sunlight as heat.

Once captured, the energy from sunlight must be stored for later use. That requires thermal mass, the third element of passive solar design. Consisting of materials that retain the heat produced by sunlight, thermal mass is the material behind or below the exposed absorber surface. It’s often a concrete slab, brick wall or tile floor.

Thermal mass can’t heat or cool your home on its own — that’s where heat distribution, the fourth element, comes in. Heat distribution is the method by which solar heat will circulate from the collection points (aperture and absorber) and storage points (thermal mass) to different areas of the building. Some buildings may require fans, ducts and blowers to supplement natural heat transfer.

It’s imperative to use shading, the fifth element, to control the amount of sunlight your home receives in the summer. Roof overhangs or trees are popular options. A well-designed overhang will allow four hours of direct solar access during the winter while limiting it during warmer summer months. Landscaping also helps cool air near the home, as mist or dew collect on plants in the morning and evaporates. Simply open the windows to take advantage of this natural cooling effect.

In practice, effective implementation of passive design will require insulation and air sealing, careful window placement, glazing and shading, careful consideration of thermal mass and type and sometimes auxiliary heating and cooling systems.

Your Home Can Heat and Cool Itself Much of the Year

If the five design elements above are implemented correctly, your home will maintain a comfortable temperature much of the year without the need to turn on your air conditioner or furnace. The temperature range is dependent upon a variety of variables and your commitment to temperature regulation.

“We open the windows early in the day, to take advantage of the cooler morning air. The hot air rises through natural convection and exhausts itself through the windows,” says Pro.

Tip: In climates where excessive heat is a problem, a porch outside your windows can limit the amount of heat due to sunlight your house receives in the summer. A white or silver roof will reflect sunlight instead of absorbing it — yet another way to naturally control your home’s temperature.

“The most important factors to consider are the regional climate and solar rotation of the location where you plan to build or update,” says Ryan McEvoy of Gaia Development in Los Angeles, Calif., a green-building consulting company that creates cost-effective solutions for efficient sustainable buildings. Because passive solar homes rely so much on the sun’s energy, they are best suited to sunny climates such as California or Colorado, though elements of the design certainly work anywhere.

The cost savings you’ll get from passive solar design is dependent on each individual situation. “The dollars you put toward passive solar techniques will be dollars saved in the long run,” Pro says. “It just depends on the extent of the design.” On average, energy savings are between 5 percent and 50 percent, depending on the scale of passive solar elements included in your home’s design. And remember, it isn’t just for new homes; existing homes can be retrofitted to include passive solar elements.

Simple Lifestyle Changes Can Maximize Your Benefit

“Be ready to be active in your house if you want a purely passive home,” Pro says, though he believes the benefits of a passive solar lifestyle far outweigh the minor inconveniences. Pro and his wife move their bed to various rooms based on the season to take advantage of the natural heating and cooling areas in their passive solar home. If you’re willing to commit to reducing your energy consumption, a passive solar design may be ideal for you.

In addition to eco-friendly features and lower energy costs, “[Passive solar homes] are free of the semi-allergic reactions associated with unnatural heating, cooling or lighting units,” McEvoy says.

In the event of a blackout or natural disaster, a passive solar home will remain a comfortable temperature without requiring a back-up generator. Due to their sustainable construction, passive solar homes can require less maintenance than a conventional home.

As energy-conscious design becomes the norm, homebuyers can expect to find energy-saving design elements such as passive solar techniques standard in many new homes. Passive solar design helps insulate owners from rising fuel costs in the future and increases the resale value of your new house.

Obviously, there are many ways to go “passive.” Whether you hire an architect or choose to do it yourself, are building a new home or simply retrofitting your existing home to include passive solar elements, there’s a passive solar solution for everyone.