Modern technology makes it cost-effective and sensible to build a 100% solar-powered home, with no utility bills and minimal carbon footprint. At ReVision Energy, we’ve helped thousands of homeowners achieve their dream of living in a solar-powered home through new construction, whether we work directly with the homeowner, or with their builder or architect.
This guide is designed for those in the process of building a new home, though many of the concepts apply to existing homes as well. It will cover:
Maine, Massachusetts, and New Hampshire offer key economic and geographic advantages that make solar a viable option for your new construction.
While most people know that powering your home with solar is better for the environment, many don’t know that solar is a powerful economic benefit too:
Building a well-insulated and efficiently ventilated house will set you up for greater success when powering your home with solar.
The most important advice we have doesn’t even pertain to solar…it’s about the house itself. Build it better!
While building codes have gotten tougher around energy efficiency, we still think that a code-built home is far below the minimum insulation/air-tightness that any reasonable person would want. It really doesn’t cost that much more money to build a tighter, better-insulated home, and the effort to do so will result in huge savings down the road, in terms of energy bills you don’t need to pay and carbon pollution you’ll keep out of the atmosphere.
There are lots of nuances to this, but we’re generally fans of building at least to a “Pretty Good House” standard. Since this term was thought up, there have been numerous resources and guide published about how to build a Pretty Good House. We recommend you check those out!
For context, a home built to this standard may command a 26% cost premium over a barely-meets-code build home, but will use roughly ½ as much energy. It’s worth remembering: A code-built house is literally the worst house you are legally allowed to build in your region… A far cry from the best! (Thanks to Emily Mottram for this particular line)
New construction requires a mechanical ventilation strategy. The more air-tight and insulated a home is, the less energy needed to heat and cool it. Naturally, such a house will also “breathe” less; to be a healthy environment for people and pets, every house needs to be able to exchange stale air for fresh outdoor air.
Building codes in most states mandate that one third of the stale air inside a home should be replaced with fresh air from the outdoors every hour, also known as the baseline Air Exchange Rate (ACH) of .3 ACH per hour.
Older, draftier homes do this by leaking air from walls, doors, windows, attics, and basements. However, as you might imagine, they lose an awful lot of heat in the process. The solution is to “build tight and ventilate right.” A Balanced Mechanical Ventilation system ensures that the right amount of potentially toxic indoor air is replaced with precisely the same amount of fresh outdoor air each hour. Energy Recovery Ventilation (ERV) and Heat Recovery Ventilation (HRV) systems improve on this concept by extracting heat from the outgoing stale air, keeping it inside the house. Thus, the needed air changes can occur with minimal loss of BTUs!
There are several configurations and brands of ventilation systems, which have varying levels of efficiency. The least efficient will only preserve around 50% of the heat from the exhaust air (and often even less if improperly installed). At ReVision, we only work with the best products in every technology, and exclusively install Zehnder Energy Recovery Systems.
Zehnder, based in Italy, is a leading manufacturer of ventilation equipment in Europe, where standards for energy efficiency have been higher than in the US for some time. The ComfoQ ERVs from Zehnder offer up to 90% efficient heat recovery – significantly more than most domestic ventilation systems.
Our team would be happy to guide you as you consider ventilation systems for your new construction.
The location, orientation, and design of your roof is a key factor in building your solar powered home - if you're planning on rooftop solar, of course.
The roof matters!! Some decisions around how you design and orient your home can have big impacts on solar. Some key considerations:
Finally, the good part! There are different ways to go solar (off-grid, grid-tied, etc.) but for this guide, we’re going to assume you’re going with a grid-tied solar options. Here's why:
In a grid-tied solar electric system, with or without battery backup, the goal is generally to achieve net-zero, meaning, at the end of the year your home will have produced as much electricity as it has consumed. This is not always possible (especially if you’re heating with solar and also running an electric car) but it’s a worthy goal!
Before we get into heating and cooling, we start with getting an estimate for ‘plug loads’ — the amount of power you need for your household appliances, electronics, well pump, etc.
This is tricky! No two families are alike, and two families living in the same home can have VERY different electricity bills depending on occupant behavior. Once you start to work with a ReVision Solar Design Specialist, we’ll do a more thorough analysis, and ideally get a professional energy designer in the mix to build a more complex model. Some useful terminology for you to know:
Modern heat pumps are fundamentally more efficient than older technologies like baseboard heating and air conditioning and a great option for new construction.
Do you dread the idea of putting a noisy, fuel-sucking heater or boiler into your new home? Well, good news! Your solar-powered home of the future needs no oil or gas at all. Modern heat pumps, which can be powered by solar, are the best option for you newly constructed homes (old homes too, for that matter).
Cold-climate heat pumps work by using a refrigeration process similar to the way your home’s refrigerator works. Warmth is extracted from the ambient outside air (down to temperatures around -15F) and transferred into your home. Since the heat pump is moving, not creating, heat, it is highly efficient. Powered by solar, a heat pump can heat your home for the equivalent of around $1/gallon for oil!
Heat pumps also replace the need for air conditioning. In warmer months, heat pumps extract hot air and humidity from your home, for less than what a typical air conditioning unit costs to generate cool air.
While it’s possible to keep drafty old homes warm with heat pumps, they are far more effective when used in a tight, well-insulated house, hence our recommendation that you build one. If you build a good quality house, then you can heat primarily with heat pumps, and install a small backup system (say a pellet stove or electric baseboard) to supplement the heat pumps during periods of extreme cold weather.
Since heat pumps are powered by electricity, you can use solar power you bank in the summertime as your fuel source in the winter.
If you're planning on building a new home and want to harness the power of the sun to create an energy efficient, climate friendly household, get in touch with ReVision! Use the Get Started button below to contact our Solar Advisor team.