New construction projects present opportunities to plan ahead for a solar or battery power system. Here are the point-by-point subjects of interest for planning ahead.
Planning. For new construction, we can start advising as soon as building plans are available. We can then determine the size of a system to fit the home and provide an initial estimate. We can perform some electrical work during the rough-in phase (when framing is complete), and will usually wait until construction is complete (or nearly complete) before the main installation.
Electrical. During the rough-in phase, a conduit for a solar circuit can be installed, whether from the attic or a ground mount. More significantly, the main utility service connection to the home and the main breaker panel can be planned for a backup power installation, reducing retrofit costs. Backup power systems intercept the main service wire between the utility meter and the main breaker panel (similar to a transfer switch used for a whole-home standby generator). Otherwise, the home may be partially backed up by installing a secondary breaker panel and separating backup circuits.
Efficiency. Conventional building practices do not often aim for the highest standards of energy efficiency. Ensure your contractor is aware that air-sealing and insulation are important to you. Modern building methods and materials can greatly conserve energy and enhance energy efficiency (and comfort), at an upfront cost for quality that will provide a return on investment.
Envelope/Insulation. The largest energy requirement for most buildings is heating and cooling, so insulation and air-tightness are typically the most significant aspects of building efficiency, especially in winter climates. This is especially true for solar-powered homes that want to be fully self-powered for the winter (when there is the least sunshine).
Ventilation. An airtight building envelope requires mechanical air exchange, air filtration, and humidity control. Energy recovery ventilation systems perform these tasks in a single system (an ERV), which is necessary for achieving air quality control within a sealed building envelope. This also provides a much higher quality environment and air quality than a conventional "leaky" home. Whole-house ventilation fans are another excellent option.
Heating/Cooling. Heat pump technology both heats and cools the home very efficiently and is an excellent choice to cover most of the heating needs for the year. There are a variety of heat pump systems to choose from based on your building needs. Some heat pumps also offer auxiliary electric resistive heating elements for additional power when the heat pump becomes less efficient in extreme cold.
Appliances. Most new appliances now score very well on efficiency, so it's not really necessary to install the most efficient or expensive version of all major appliances. But if you are aiming for the lowest energy requirement and cutting-edge options, learn more about appliance selection in our Off-Grid post.
Roof. Most homes have a large enough roof to accommodate a sufficient number of solar panels, but not necessarily enough space to be energy independent. The suitable roof space must face a southerly direction. Less complex roofs (with fewer hips and valleys) are favorable. Pipes, flues, and vents should all be positioned out of the way (north side) of the solar panel area (south side). Solar panel mounting hardware can accommodate almost any roofing type, but some options are preferable to others. For a typical home, about 300 square feet of solar panels are needed to cover half of the electric use. Plan drawings can be sent to us to determine the solar capacity of your design. Learn more about roof mounting in our rooftop post.
Ground mount. When the roof option is unfavorable or if maximum winter performance is required, a ground-based solar option may be considered when there is a suitable location and terrain to work with. Ground mounts add a sizeable amount of additional material and work, but also improved solar performance and accessibility. Learn more about ground mounting in our ground mount post.
Battery location. Batteries must be installed in a space like a garage or a mechanical room, or other conditioned space indoors where the temperature is between 50 to 85 degrees Fahrenheit for most of the year (32 degrees is the minimum). The ideal installation setting is located near the primary electrical service and breaker panel, though circuits for the battery can be installed between an attached garage and a mechanical room in some cases. In most cases, the battery cannot be installed in a detached garage, unless the detached garage is where the primary electrical service is located.
Generator. If a backup generator is desired, it can be incorporated as a backup to a battery system. In some cases, a transfer switch is still used, but not always. The generator will take over when the grid is out and the battery is empty, or the generator can be used to charge the battery, depending on the situation. When there is no battery, the solar power system will operate only when there is grid power and the generator will power everything when the grid is out.
Utility. Though you will not be able to choose your utility provider, you may have some discretion over the type of service you will be paying. Each provider has a unique set of options. In most cases, a regular residential or total electric service is preferred. In situations with batteries, a demand charge or time of use rate may be more suitable. For utilities that offer an electric heat rate (discount), the heat rate may not be compatible when a solar or battery power system is installed. Learn more about utility rates in our post about the local electric utility providers.
We hope these tips have been useful to help you through your planning stages. We try to present everything you need to know here on our website, but when you need further assistance feel free to contact us.