ZNE Homes: Energy Production > Energy Consumption
As municipalities across the country tighten their energy and building codes, some builders and homeowners will be mandated to improve the energy efficiency of their residences and reduce carbon emissions via electrification, renewables, high efficiency appliances, and high-performance building products. Some are going as far as building zero net energy (ZNE) or zero net energy ready homes to get ahead of the curve. Zero net energy homes seek to balance energy consumption by increasing the home’s energy efficiency and by using renewable energy generated on site, producing as much energy annually as they consume.

Building zero net energy is not just a passing trend – we are at a true inflection point in market adoption. The Energy & Environmental Building Alliance (EEBA) maintains an inventory of zero net energy homes in the U.S. and Canada and the latest report from 2022 shows 190% growth in total projects as well as 440% growth in single family houses.

Leverage High-Efficiency Propane Systems to Offset Electricity Use

While some ZNE projects will be all-electric, high-efficiency propane systems can be leveraged as well to reduce emissions while meeting energy needs. Propane is a clean, nontoxic, efficient, and affordable energy source that is highly versatile. It can even be used in conjunction with renewable energy sources such as solar and wind to lower utility bills while still providing homeowners the benefits of gas appliances such as propane-powered stoves and dryers. When designing and building a ZNE home, you should be aware of the space heating, water heating, back-up power generation, and amenity options available to you with propane.

“There are a lot of zero net energy projects going on across the country, and we can only assume that the numbers will increase year after year with new energy code requirements. The goal is to make these homes as energy efficient as possible and decrease the amount of electricity and gas they need to use because they are built so efficiently.”

– Matt Evans, Newport Ventures

Heating system options that can improve heating loads while reducing carbon emissions include high-efficiency propane furnaces, heat pumps, and hybrid heat pump-furnace combination systems (also called dual-fuel systems), which can optimize the performance of both systems. High-efficiency propane furnaces offer Annual Fuel Utilization Efficiency (AFUE) ratings as high as 98%, which is a standard measurement of how efficiently a furnace converts energy from the fuel it uses into warm air for a building.

Water heating is also a significant portion of a home’s energy budget, so choosing high-performance options such as propane tankless water heaters, heat pump water heaters, high-efficiency tank systems, and mixed-fuel hybrid systems help homeowners save energy and utility costs. Mixed-fuel hybrid systems incorporate a propane system like a propane storage tank water heater with complementary technology such as a solar water heating system. Propane can be used for other amenities inside and outside the home such as fire pits, pool heaters, and snow melt systems to optimize function, lower a home’s energy consumption, and make it easier to achieve sustainability goals.

With much of the home running on electricity, it is critical to have a backup power source. Propane powered backup generators will keep the lights on, the HVAC humming, and the refrigerator running in case of a power outage. When contemplating building a highly efficient zero net energy home, or even a zero net energy ready home, builders and homeowners would be wise to include propane as an important part of the energy mix to balance performance and sustainability.

Rate and Market Your Homes with HERS

The Home Energy Rating System (HERS) Index is used to measure efficiency and can be determined before a house is even built via modeling, then confirmed after completion. The more energy efficient a home is, the lower the HERS Index score, which ranges from 0 to 150. The standard new home built to 2006 IECC code scores around 100 points. Homes built to more stringent codes have moved down that scale with homes built to the 2018 IECC achieving a score around 70. A ZNE home scores 9 points, with some homes even going into the negatives on this scale. The HERS Index is a great way for national and regional builders to rate and market their homes.

Project Highlight1
The 2022 New American Remodel is a 1963 mid century modern home in Orlando, FL that doubled in size and sought to optimize energy efficiency. Drew Smith, COO of Two Trails, the energy rater and sustainability consultant on the project, helped to lower the project’s HERS Index score from 115 (original house) to -22 (remodeled house) and achieve zero net energy. This was accomplished partially through the use of propane appliances and amenities such as linear propane fireplaces, a propane-fueled outdoor grill, and a pool with a propane heater. In addition, five propane tankless units were installed to
meet the large water demands of the home’s multi-fixture shower systems, and a propane standby generator enhances resilience, a key safety feature in hurricane-prone Florida.

Zero Net Energy Homes Powered by Propane
When designing and building a ZNE home, electricity and renewables aren’t the only answer for powering the residence cleanly and efficiently. Propane-powered systems and amenities are a key partner in reducing carbon emissions and boosting the energy efficiency of these next-generation homes.

Learn more about building with propane.

1 Designing the Zero Net Energy New American Homes (suburbanpropane.com)