New construction projects present opportunities to plan 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. We will advise regarding the main utility service connection to the home and the main breaker panel (whether installed by us or others). During the rough-in phase we may install conduits for a solar circuit. For backup power systems, the main service wire between the utility meter and the main breaker panel may need to be intercepted by a backup switch (similar to a transfer switch used for a whole home standby generator). We will advise accordingly. Conventional wiring methods do not typically plan ahead for a backup system retrofit, so planning accordingly will reduce rewiring costs for a future addition of a battery system.
Efficiency. Conventional building practices do not often aim for the highest standards of energy efficiency (or favor cost efficiency instead). 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.
Insulation. Because the largest energy requirement for most buildings is typically related to heating and cooling, insulation and a quality building envelope (air-tightness) are 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).
Heating/Cooling. Options for HVAC systems range widely and are one of the most important considerations in new construction. 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 numerous options available. In very cold climates, a more energy-intensive system such as a gas furnace or woodstove will also be an important backup/alternative heat source when it's needed most.
Ventilation. Building to achieve the most energy-efficient home also aligns with producing a more comfortable and healthy home environment. To achieve a higher standard of efficiency in the building envelope, air exchange, air filtration, and humidity control are essential. 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.
Appliances. High-efficiency appliances are another important factor, and thankfully most new appliances score very well on efficiency and it's not strictly necessary to get the most expensive or efficient version of everything. Additional information on appliances selection is detailed in our Off-Grid post.
Building size. Larger homes will inherently need more energy than others, but may also provide a larger roof space for solar and therefore a greater economy-of-scale for the power system. However, homes that are designed smaller and to a higher degree of efficiency can be more affordable and require less energy. At the smallest scale, "tiny" homes may require very little power but may also lack adequate space for solar panels and batteries.
Roof. Learn more about roof mounting in our rooftop post. In general, less complex roofs are favorable, and pipes, flues, and vents should all be positioned out of the way (north side) of the solar panel area (south side). Most any type of roofing material can be used, but some are preferable to others. For a typical home, about 300 square feet of solar panels is needed to cover half of the electric use. Plan drawings can be sent to us to determine the solar capacity of your design.
Battery location. You may be considering a solar power system without batteries or adding batteries later. Batteries must be installed in a space like a garage or a mechanical room, or other conditioned space indoors. The ideal installation setting has the electrical service, energy system (solar and battery equipment), and main breaker panel located at one location in a garage.
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.
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.