When most people think about net-zero homes, they usually think of solar panels and battery storage systems. However, creating a net-zero home is a holistic process that must take into account a wide variety of materials and technologies.
HVAC systems (Heating, Ventilation, and Air Conditioning) can play a particularly important role in reducing your home’s overall emissions — but that doesn’t necessarily mean buying smart thermostats or other fancy new technology. Instead, you might just want to concentrate on making sure your existing HVAC infrastructure is properly maintained and energy efficient.
Energy Efficiency: a Must for Net-Zero Homes
Before we can go any further, it’s important that we clear up a common misconception about net-zero homes. Too often, people hear the term and assume that net-zero homes must produce no carbon whatsoever — a fundamental misunderstanding of the concept. “Net-zero” simply means that the emissions a home does produce are offset by the emissions it takes out of the atmosphere. In other words, making a home more energy efficient can be just as important as helping it produce its own clean energy via technology like solar panels and battery storage systems.
According to Natural Resources Canada, 56% of all energy used in residential and commercial buildings goes towards space heating, while an additional 5% is used for cooling. With so much energy spent on climate control, improving HVAC efficiency can have an incredible impact on any building owner’s efforts to achieve net-zero status.
Common Questions on HVAC Efficiency
We’ve put together a list of common questions about how to improve HVAC efficiency in your home. Look over the following information carefully, and use it to make sure your HVAC never uses more energy than necessary.
How Often Does My HVAC Need Professional Maintenance?
There are differing opinions on this, but the general rule of thumb is that HVAC systems should undergo professional maintenance about once a year.
Don’t wait until your system starts exhibiting obvious problems, as these will more than likely require extensive (and expensive) solutions. It’s far more cost-and-carbon-effective to prevent major problems than it is to solve them once they’ve already occurred. Having a professional visit your home each year to run diagnostics and tune up small issues will ensure that your system is always operating at peak efficiency and that impending problems can be nipped in the bud.
What Can I Do Between Service Calls to Keep My HVAC Efficient?
Don’t foist the entire burden of HVAC maintenance onto a professional contractor either — there are actually lots of things you can do by yourself to keep your system in tip-top shape. For example, we recommend:
- Performing weekly walkarounds of your property during warmer weather, and moving debris like sticks or leaves at least two feet away from your outdoor unit so as to prevent clogs that might otherwise fall inside and block the flow of air.
- Checking the seals on all exterior windows in your home for leaks on an annual basis.
- Making sure your thermostat is set to the correct temperature, and that you are checking its batteries on a regular basis.
- Changing your HVAC filters every 3 months.
What Do Measurements Like SEER and EER Mean?
If you’re in the market for a new air conditioner, you’ll probably see the acronyms SEER and EER on any product you consider. Note, however, that these are different scales of measurement for determining the efficiency of a unit.
EER (Energy Efficiency Ratio) is arrived at by simply dividing it’s BTU (cooling power) by its wattage (the amount of electricity it uses).
SEER (Seasonal Energy Efficiency Ratio) is found by dividing the unit’s BTU per hour during a given cooling season by the total number of watts per hour it uses over that period. As such, SEER is more important to consider when assessing the efficiency of an air conditioner throughout an entire season, whereas EER reflects the efficiency of the unit during peak hours in a given day.
Both are important to weigh when purchasing a new AC, although SEER will be more useful in regions with a balanced climate since it was specifically designed to assess the seasonal efficiency of systems in the central United States.
What Kind of Filters Should I Use?
Changing your furnace filters out regularly is only one part of effective filter maintenance. You may also want to consider what kind of filters your system uses. Filters have different MERV ratings between 1 and 16, with higher numbers filtering out more particles but reducing overall airflow.
Most filters for home furnaces should be rated from 8 to 11 to make sure they adequately protect your blower fan without blocking too much air and forcing the system to overwork itself — which reduces efficiency and can cause malfunctions.
What Kind of Water Heater is Best for My Home?
Ducts, furnaces, and air conditioners aren’t the only important components of a home HVAC system. You’ll also need to think about your water heater — since a lot of energy gets spent heating and storing water for later use. Instead of a traditional water heater, it might be worth investing in a tankless water system that only heats water when it’s actually needed. These can be 24-34% more energy efficient than standard water heaters in homes with modest hot water needs (although they tend to be quite expensive at the point of purchase).
Many Roads to HVAC Efficiency
Since HVAC equipment tends to account for so much of any given home’s energy usage, even a few simple changes to your system can go a long way towards achieving net-zero status. Producing your own electricity is just one of many ways to reduce emissions.
From replacing your water heater or air conditioner with a high-efficiency model to changing your furnace filters and arranging regular maintenance on your system, there are plenty of ways to help make your HVAC work towards your goal of a net-zero emission household.