Elon Musk, Tesla CEO and SolarCity chairman recently unveiled a new type of roofing tiles, which are also solar panels. It’s no secret that the Tesla company is rapidly developing new ways of establishing a more sustainable future, and these roofing tiles are a great idea. They would be used to cover a roof just like regular tiles, and thereby incorporate solar energy harvesting potential directly into any home without the need to spend money on and install a separate solar power array.
These solar tiles are made of glass and come in many different styles, including textured tiles, French slate, flat modern and Tuscan style curved roof tiles. Every tile appears opaque when looking at it from ground level, so the solar cells inside it would only be visible from the air.
The main goal of this project was to develop rooftop solar arrays, which would be more aesthetically pleasing than currently available ones. And by having the solar panels also act as roofing tiles, the whole system would also be much more affordable than currently available solutions. The tiles they created in some cases look even nicer than regular ones, while they also last longer, provide better insulation and, according to Musk, “Have an installed cost that is less than a normal roof plus the cost of electricity.”
Tiles made of glass might not sound very durable, but they tested their durability by dropping a weight onto a roof covered in them from above. The tiles did not shatter as traditional roofing tiles do in such a test, but only cracked. They did not yet announce the price of these tiles, or their energy generation and insulation value. But it is a project well worth following as it goes forward.
Apart from introducing these new solar roof tiles, Tesla also announced the second generation of their Powerwall battery. The so-called Powerwall 2 is basically a battery pack, which is capable of providing 14 kWh of storage. This is enough to provide sufficient power for everything needed in a four-bedroom home for a day. Hooked up to a rooftop mounted solar system, it could in theory be used to power a home for quite a long time. The Powerwall 2 costs $5,500 and they will begin taking orders for it soon. Its development is a joint effort between Tesla and SolarCity.
Passive homes tend to be a little boxy and unappealing, which is probably the reason they haven’t caught on as much as they could. So it’s nice to see companies finding ways around that. One such example is certainly the Cousins River Residence, which was designed by GO Logic of Maine. This firm has been making prefab and passivhaus homes for a while now, and the simple elegance of their designs sets them apart from others.
The Cousins River Residence is located in Freeport, Maine. It measures 1600 square feet designed and was built to Passivhaus standards. It is very well insulated with the foundation having a rating of R35, the wall R50, and roof R80. It was also fitted with high performance triple pane German windows, which provide 50% solar heat gain and have a rating of R8. The home also features a heat recovery ventilation system that boasts of an 88% efficiency. The shell of the home is airtight and provides 0.5 air changes per hour at 50 Pa. The home is also near net-zero, and features a rooftop mounted 4.6 KW Photovoltaic array, which takes care of the remaining energy needs.
The specs are great, but what’s also very impressive is that the home is modern architecture at it’s best. The shape of a home is simple enough to blend in seamlessly in any environment, and the color palette they chose is mostly whites and naturals. The single story home features a large living and dining area, with a spacious kitchen at one end. One of the walls of this area is covered by glass doors that let in plenty of natural light into the home, which is something not often seen in passive homes.
The home also features a wooden deck, a screened-in porch as well as a covered walkway. One of the main aims the designers had when planning the home was to provide freedom of movement both inside the home, and between the interior and exterior. They also designed it so that it is easily accessible for both the young and the old, since the current owners plan to spend a long time living in it.
Mark Jacobson, a professor at Stanford University, California recently commissioned the Canadian firm Bone Structure to build him a prefab net-zero home. And the result is shaping up to be quite astounding. He chose the company because of their proven ability to minimize construction waste, dust and disruption to neighbors, as well as the flexibility and versatility of its steel frame construction method.
The home measures 3,200-sq ft (297-sq m), which is quite large for a net-zero home. The columns and beams needed for framing were precision laser cut at a factory before being transported to the build site and assembled. In this way they were able to make the most of the oddly shaped lot on which the home is built, and achieve an interior layout, which would simply not be possible using traditional construction methods.
Constructing the frame was done in only a few days by five workers using just battery-powered drills and a single type of self-tapping screw, which were used to attach the columns and beams. The next step was installing the electrical, plumbing, heating and ventilation systems, which was made easier by the precut openings in the frame. Once this was achieved, precut insulation panels were clipped into place between the steel columns. Polyurethane foam insulation spray was used to seal the building and act as a vapor barrier. According to the company, a shell like this leaves practically no waste, is fully recyclable and creates a tight, energy-efficient building envelope.
The home is still being constructed, though it will be available to tour on June 24-26. Once completed, the home will be powered solely by electricity (i.e. no gas or other sources). They will install heat pumps for air and water heating, use an induction stove, and all the necessary power will be provided by rooftop-mounted solar panels, with the excess energy stored using Tesla batteries.
Bone Structure is planning to build 50 more homes in the area in the next year.
Unity Homes has recently unveiled a prefab home, which is sustainable yet still made to last for at least as long as traditionally constructed homes. The home has a number of certifications, including LEED v4 Platinum, while it is also net-zero energy and can be constructed on site in three days or less. It is also fitted with the largest number of Cradle to Cradle (C2C) certified building products used in a residential project to date.
This so-called Zūm model was built in collaboration with BUILDER magazine and the Cradle to Cradle Products Innovation Institute. The demo home pictured above, which was exhibited at the 2015 Greenbuild event, was made in the company’s factory in New Hampshire in just five weeks. It measures 1,620-square-feet, and features two bedrooms and two bathrooms. On the Expo floor, the shell was built in a day and a half, and the rest, including the furnishings and additions took an extra two days.
The home is insulated using GreenFiber Cel-Pak cellulose insulation, which is made of 85% recycled paper fibers. To create the home’s airtight envelope, which targets .6 ACH50, they used Huber Engineered Woods’ ZIP Systems wall and roofing panels. The home is also fitted with fully operable triple-glazed unplasticized PVC (uPVC) Intus windows. The home is equipped with a Zehnder ComfoSystems CA 200 heat recovery and ventilation system, which works to provide an uninterrupted flow of fresh air into the home.
Furthermore, the home is fitted with SunPower solar panels, which are the only solar panels to have received C2C certification. They are made completely out of non-hazardous materials and come with an energy meter and app. This is only one of many C2C materials and products used to build the home.
According to the company, they can build one of these homes in just 30 days yet they will be around for 300 years. They also use no fossil-fuels in the building process. Unity Homes wish to offer affordable as well as sustainable homes, so this prefab is priced at under $150 per square foot. This number could still drop to under $140 per square foot in 2016.
Holly & Smith Architects, a firm out of Louisiana, have recently finished the so-called Pond House. As the name suggests, this home is located right near a pond on a 15.5 acre (6.27 hectare) plot of land in Louisiana, USA. It’s both luxurious and energy-efficient, so much so that the designers are sure it will be net-zero once they are done testing and tweaking it.
Pond House is a three-story house and measures 1,250 sq ft (116 sq m). It is a rather angular structure made up of two protruding volumes. The cladding of the home is actually limestone-textured stucco and polycarbonate panels. This produces a very interesting effect at night, making the whole house glow like a lantern when all the lights are on.
The ground floor features an outdoor area with a fireplace and outdoor kitchen. The main living area, as well as the kitchen and dining room are located on the first floor while the top floor houses the master bedroom, bathroom and terrace.
The home features a 14-degree sloping roof, which is fitted with a solar power array. The roof was designed to also channel rainwater runoff into the pond below. In addition to this the home is also equipped with a geothermal heat pump, LED lighting, and spray foam insulation. For better ventilation, the home was also fitted with fully operable windows placed strategically throughout the home.
Pond House is not quite a net-zero home yet, but it is very close. In the last ten months since it was built, it only needed to draw 870 kWh over net zero of power from the grid, which totaled about $250 in electricity bills. The architects are confident that net zero status will be achieved soon, as they continue to adjust the home’s lighting and temperature settings.