Buildings contribute significantly to greenhouse gas emissions, so incorporating green building materials in new construction and remodeling is essential. Fortunately, advances in solar-responsive building materials are making it easier to achieve a more sustainable future.
Photovoltaic technologies now blend seamlessly with traditional building materials, eliminating the visual disconnect between energy generation and architecture. These advancements also provide a number of aesthetically pleasing options for sustainable design.
Insulated Window Coverings
Adding insulated window coverings to your home can prevent unwanted heat gain in summer and reduce heating loss during winter. Insulated window blinds and shades, especially those with a honeycomb design, trap pockets of air that effectively insulate windows at the point of contact.
Many insulated window shades, particularly those that fit into side tracks and can be adjusted from both the top and bottom, can increase the R-value of windows by 40% or more when tightly installed. They can also protect against UV damage and glare while allowing some daylight to pass through.
Another energy-efficient option is a low-e window film, which helps to improve thermal performance by blocking near IR solar radiation. Window films can be professionally applied or bought as do-it-yourself products at home improvement stores. However, it’s important to note that window films can void a window manufacturer’s warranty. They can also block some natural sunlight, which may not be desirable in warmer climates.
Passive Solar Design
Passive solar design uses natural processes to heat and cool buildings, rather than relying on specialized equipment driven by electricity or gas. It takes advantage of the sun’s direct and radiant heat energy, utilizing materials that reflect, transmit, or absorb solar radiation, and air movement mechanisms such as conduction and natural convection.
These building materials include thermal mass that can store heat, as well as insulated walls and ceilings. They also incorporate shading devices, such as awnings and louvers, to control the amount of sunlight entering a room during summer and to prevent glare, and ventilation systems that promote cross-ventilation to expel hot air and draw in cooler air, reducing the need for artificial cooling.
Daylighting also contributes to passive solar design, and careful planning can ensure that the amount of artificial light is just right for a room or space to maintain proper illumination levels without over-stimulation and causing fatigue. Additionally, it reduces the need for power-hungry lighting equipment.
Awnings and External Blinds
Awnings and external blinds help reduce solar heat gain by shading windows. They also keep out the sun’s glare and protect indoor spaces from rain and wind. They are available in a range of colours, fabrics and styles that can be custom-made to suit any aesthetic.
They are a good option for east- and west-facing windows, which are difficult to shade with traditional window coverings. They are easy to use and offer advanced weather protection. Some can be rolled up in winter to allow lower angle sunlight into rooms.
However, they may block outdoor views. This is a disadvantage if you are used to looking out your windows at the trees and sky or want to make sure you can see your neighbour’s house. They also need to be regularly cleaned to avoid dirt build-up. Some awnings are motorised for ease of operation. They can also be fixed to a rail or wall, which makes them more stable in high winds.
Building-Integrated Organic Photovoltaics
OPV (organic photovoltaics) solar cells convert sunlight into electricity using organic materials. They are lightweight and semi-transparent, enabling architects to incorporate them into the building design without compromising on natural light penetration. The thin film can be made with a range of colours, and anti-reflection coatings allow the cell to capture more sunlight. It can also be produced on a roll-to-roll basis using small-molecule solutions, reducing production costs and making it accessible to the commercial market.
BIPV integrates solar PV into the exterior of a building or cladding. The system serves as the outer layer of the structure and generates power for on-site consumption or export to the grid, while simultaneously lowering energy costs and improving aesthetics. Respondents indicated that the largest opportunities for BIPV were in the commercial segment, particularly in office buildings and stores. However, residential buildings were also perceived to present an opportunity if the PV products can be made more attractive than conventional rooftop systems.
Solar Panels
A solar panel converts sunlight directly into electricity to power homes, and heats buildings in winter. Large solar panels also provide power to utility companies and large businesses.
Solar energy is a clean, renewable resource that provides an alternative to fossil fuels. It produces far fewer greenhouse gas emissions during its lifetime than traditional energy sources.
Solar cells contain two layers of silicon, one layer called P-type (silicon plus boron) and another called N-type (silicon plus phosphorus). When the solar cell is exposed to direct sunlight, it creates an electric current. The electrons flow from the negative side of the circuit to the positive side, powering a lamp or other device.
Solar panels are connected to other cells in series and in parallel to boost their voltage or current capability, forming modules. Modules are then wired together and framed to form a solar installation known as a PV system.
Solar Roof Tiles
Solar roof tiles, or solar shingles, are photovoltaic panels designed to look like traditional roofing materials. They’re known for their ability to blend seamlessly with the rest of a roof, making them an aesthetically appealing and unobtrusive way to generate power.
They’re also more durable than traditional photovoltaic panels. They can withstand heavy rain and winds of up to 130 mph, making them an excellent choice for hurricane-prone areas. They can even withstand snow, although it’s best to keep them clear of debris and moderately clean to ensure optimal performance.
However, a downside to solar roof tiles is that they can be more challenging to transfer when homeowners move house. This is because they replace conventional shingles rather than being mounted on top of them. They’re also more expensive than solar panels and require skilled labor for installation. This makes them more suitable for new construction and for those who are planning to build a green home from the ground up.