Building a net-zero energy house: What homeowners need to know

The cost of old-school power just keeps going up.

California prides itself on environmentally friendly policy. In recent years, new legislation has emphasized renewable energy. Several cities have banned or restricted natural gas in homes. The state now requires solar panels on new residences. 

The policies are a good start, but the state’s energy situation is far from ideal.

Every summer, California makes national headlines with rolling blackouts because the grid just can’t handle the strain.

On top of that, the cost of electricity is rising much faster in California than in the rest of the US. The average retail price of residential energy steadily increased from 12.09 cents per kilowatt hour in 2001 to 19.15 cents per kilowatt hour in 2019. 

The outdated way of powering our homes is costing us big, both in dollars and in environmental damage.

At New Avenue, we believe in the bigger picture. If we’re ever going to get a handle on climate change and wean ourselves off of fossil fuels, the way we power our lives is going to have to change. A huge part of that is powering our homes.

That, we can do something about.

What does it take to build a net-zero energy home? (It’s not just about solar panels)

Designing a home that is net-zero or even net-positive is a three step process:

1 - Passive design: By carefully studying the site, your designer can take advantage of the sun, the shade, the wind, and other aspects of the environment to control the climate in your home. Smart orientation of the building can block cold winds in the winter and use natural ventilation to cool the home in the summer. Window placement and roof shape can help harness the sun’s rays for natural warmth. Materials like concrete and stone can store heat during the day and release it at night to keep your space warm. 

Efficient windows, doors, and insulation help to maintain a comfortable indoor environment. Airtight construction, high-performance glazing, and thermal-bridge-free detailing are all essential elements of an energy-efficient home, keeping the indoor air comfortable and minimizing waste.

2 - Active systems design: Once we optimize the design of the home to reduce the need to heat and cool it, we then find the most sustainable “active” HVAC systems. These include systems that use heat recovery (the hot air leaving the home can pre-heat the air coming in) and economies of scale (can one heating system serve multiple rooms?) to help reduce the need to use energy. New technologies like smart thermostats will help as well, efficiently controlling system use.

3 - On-site energy generation: Next, it’s time to create an energy budget. We tally all the energy the home needs—AC, fridge, lights, phones—everything. We then design a solar strategy that will power it all. We also look into batteries like the Tesla PowerWall, which can store excess energy for use later (at night, for example). If your home gathers as much energy as it uses, it’s a net-zero energy home. Any excess energy can be sold back to the grid (which makes it net-positive). If you’re using solar power for an accessory dwelling, you can use the excess to power your main home and further reduce your impact.

What are the up-and-coming technologies that are making a difference in energy consumption?

Dedicated ventilation systems for heat recovery and air filtration are particularly important today. This is especially pertinent in California, with wildfire smoke becoming a more common occurrence every year. Proper air quality is one often-overlooked part of building designs, especially in residential construction.

We are excited about the potential of having both high- and low-voltage circuits in homes to improve energy efficiency. Normally, a house runs with 120-volt lines everywhere, but it’s possible to run low-voltage lines through the house, too. LEDs can run on the standard 120 volts, but that’s actually too much for them. That’s why they have circuitry to step the voltage down.

You lose a lot of energy making that conversion. But with low voltage lines in the home, you can convert electricity to a direct current to provide highly efficient lighting with less energy loss.

What about costs?

At New Avenue, we’ve noticed a common thread when discussing net-zero-energy with clients: the initial cost can be surprising. 

On-site power, energy-saving construction, and efficient appliances mean higher up-front costs and greater long-term savings. Many of the more efficient appliances come with a premium price tag. However, the industry is shifting to meet efficiency demands. 

The bottom line: The initial costs are high, but with proper planning and value engineering, net-zero can be affordable.

What should California homeowners know about net-zero energy design and construction?

First, it’s important to understand the importance and urgency of building energy-efficient homes. With the risks of climate change and its adverse effects on the environment, net-zero energy design should be at the forefront of homeowners’ minds. Not only will it save them money over the long run, but the design concepts will also lead to a more comfortable built environment.

Second, homeowners should understand Title 24. New homes and ADUs are required to include solar power, so becoming net-zero for a new ADU is part of the game. People need to know that it will cost to add efficient appliances and solar systems so they’re not surprised when a system costs almost $15,000. Some tax benefits and incentives are running out soon, so it is a good time to look into solar.

(Editor’s note: The federal Investment Tax Credit (ITC), will allow you to deduct 22% of the cost of a solar energy system from your 2021 federal income tax. The state of California is offering a new construction exclusion for installing certain solar technologies through 2024.)

One of our current projects is a home that will be very close to net-zero energy. It will consume more energy than it produces in the winter months, but that energy consumption will be offset during the summer.

Still have questions?

Whether you’re ready to jump in or need more information, you can get in touch with our licensed, experienced experts by clicking the button below to schedule a free call. We’ll call you and answer all your questions. When you’re ready, we’ll schedule a contactless design/build meeting with the team that’s best for your project.

Let’s make a difference together.