Designing and building a new home for energy independence has become a compelling goal for many homeowners, with environmental consciousness and energy efficiency at the forefront of today’s societal concerns. By incorporating sustainable and renewable energy solutions, from the initial design phase through construction, you can build a home that not only reduces your family’s carbon footprint but also delivers long-term cost energy savings and sustainability.
In this article, we will explore the key considerations, strategies, and technologies, and the process involved in designing and building your energy-independent home.
What is energy independence?
When it comes to designing your home, energy independence refers to your ability to generate, store, and manage sufficient energy on-site to meet your household’s needs without relying on the power grid. This doesn’t mean that your home must be off-grid in the back woods, or that you can’t include net metering in your home’s energy strategy. However, you should be able to count on your own stored electricity if the grid goes down due to weather events or an aging grid infrastructure.
Benefits of energy independence
Energy resilience: Your energy storage system can be paired with a net metering program. You will be able to store excess energy for later use and ensure that you can benefit from net metering, even during periods when your solar panels are not generating electricity. The specific configurations of net metering facilities that will pair with energy storage systems, that are eligible to net meter, can vary by location.
With power companies, a 100% reliability score is virtually impossible. There are several types of outages. Reactionary or ‘unplanned’ outages occur when an unexpected fault occurs in the grid. Proactive or ‘planned’ outages can occur for several reasons, including taking the system down so service teams can safely complete maintenance and upgrades to the local power grid. Momentary outages or ‘blips’ occur when the system isolates an outage to only the area directly affected by the issue, while customers who would have also experienced an extended outage in the past are restored within seconds.
There are numerous power outage causes. Adverse weather is typically the most common cause. Power distribution hardware is often exposed to the elements, and heavy rain, snow, sleet, or wind can cause damage to the grid. Defective or outdated equipment can cause outages, resulting from a factory defect on new equipment, a random failure, or failure of equipment near the end of its useful life, or equipment that is unable to handle the current demand.
Foreign interference can result in issues with lines, transformers, and other equipment. Interference can come from lightning, wildlife such as squirrels and raccoons, aerial or tree contact, vehicle accidents, salt spray and winter road maintenance, and fires.
Cost savings: Achieving energy independence with a net-zero home can significantly reduce or eliminate your energy bills, providing substantial financial relief. Owning an energy-independent home cuts your energy-related consumption costs.
A Residential Energy Storage System (ESS) can also be used in combination with BC Hydro’s net metering. Net metering is a billing mechanism that credits you for the surplus electricity you add to the grid. This allows you to export excess electricity to the grid and receive credits for it, which can be used to offset the electricity you will consume from the grid.
While adding a battery storage solution to your solar panel system will not save any additional cost over net metering, it can provide a second level of energy security, in case the grid goes down.
Energy-independent homes contribute to a cleaner environment, reducing the dependence on fossil fuels and local power, while lowering your overall carbon emissions. By generating your own clean electricity you reduce your reliance on the traditional grid, contributing to a cleaner and more sustainable environment. Solar-equipped net zero homes produce lower greenhouse gas emissions and air pollution, making your household a force for positive change.
Site selection and orientation
Selecting a site with optimal sun exposure: If you don’t already have a lot picked for your new home, you will want to conduct a solar site analysis for each property you consider for optimal sun exposure, to maximize the potential for solar energy generation. Have a solar energy professional conduct a solar site analysis to determine the amount of sunlight it receives throughout the year.
In the northern hemisphere, south-facing solar panels will generally receive the most sun. Your architect or design-build contractor will be able to tell you if the home you’re designing will a) fit on the lot, and b) can be oriented for optional sun exposure. The angle you mount your panels can affect their efficiency as well, so a heavy tree canopy or nearby buildings can affect the angle you mount the panels. You want to avoid shading from nearby trees, buildings, or other obstructions.
If possible, consider installing adjustable mounts that will allow the solar panels to be tilted to optimize their angle throughout the year. Your designer should consult with a solar energy expert to determine the best orientation and angle for the specific building lot to maximize energy production.
Wind assessment: For true energy independence, you should at least consider assessing the wind patterns on the site to evaluate the feasibility of adding wind energy generation with turbines. Wind and solar energy complement each other. Wind turbines can generate power at night, or during cloudy conditions when the sun is not shining and solar panels are less effective.
Wind turbines are more efficient at converting energy when compared to solar panels, with wind turbines coming in between 20% and 40% efficient at generating usable electricity, while solar panels have an efficiency of around 15-20%.
Wind turbines also release less CO2 into the atmosphere than solar panels, making them a cleaner energy source in terms of carbon emissions. By combining wind and solar energy, you can create a more reliable and diversified renewable energy supply, reducing dependence on any single energy source.
Geothermal feasibility: Calculating the feasibility of a closed loop, standing column well or open loop geothermal heating system, for residential implementation instead of a conventional HVAC system, may be another site consideration. Geothermal heat pump systems leverage the stable temperature of the ground to provide efficient heating and cooling for the home.
If your building site is suitable, ground-source heat pumps (GSHPs), or geothermal heat pumps (GHP), are among the most energy-efficient technologies for providing HVAC and water heating.
Passive design strategies
Super-insulation: The insulation recommendations for a net zero home in Canada are focused on designing a highly efficient building envelope to minimize heat loss and reduce energy consumption. Your net zero home may have at least double the insulation of a typical code-built house. All six sides of your net zero energy (NZE) building are sealed and wrapped with continuous insulation to create an energy-efficient home: walls, floors, and ceilings.
Energy-efficient windows: Windows in passive house and net zero homes are typically triple-glazed units, filled with argon or krypton gas, that enhance insulation and reduce heat loss. High-stability frame materials such as hollow vinyl or fibreglass, can reduce costs while eliminating thermal bridging and minimizing heat transfer.
The passive house standard places emphasis on the U-Factor and R-value of windows and doors. A lower U-Factor and higher R-value indicate better insulating properties. Energy-efficient windows should contribute to the continuous insulation of the building envelope and help maintain airtightness.
Thermal mass: Including thermal mass materials in the building envelope can help stabilize temperature shifts within the home by absorbing and storing heat energy. By day thermal mass materials can store heat that will be released on chilly winter nights. During the summer months, the thermal mass can stay cool, and coupled with overhangs and other shading, will significantly reduce the load on your heat pump or air conditioner.
Natural ventilation: Natural ventilation uses natural forces, such as wind and temperature differences, to provide air exchange in your building. Strategic placement of windows, doors and other openings can allow fresh air to enter and stale air to exit your home, reducing your reliance on a mechanical ventilation system.
Modern smart ventilation controls can open and close windows to keep the air fresh, while helping to maintain comfortable temperatures. Windows can automatically be opened before you return home to flush out stale air and prepare the space for you. Smart controls can also carefully manage ventilation in response to sensor readings, taking prevailing weather conditions and your unique ventilation requirements into consideration. During the summer, smart sensors can release excess heat through the windows, opening and closing them as required to maintain your desired temperature.
Energy-efficient appliances and lighting
ENERGY STAR certified appliances: Energy Star-certified appliances help you achieve energy independence by reducing your energy costs and consumption and reliance on the traditional grid. These appliances are independently verified to deliver the energy savings promised by the label, offering improved performance, quality, and durability.
LED lighting: LED lighting is also very energy-efficient, using at least 75% less electricity than incandescent lighting. LED bulbs last up to 25 times longer than incandescent bulbs, reducing the frequency of replacements, thereby lowering the associated energy and maintenance costs, while contributing to a more sustainable and energy-independent lifestyle.
Water conservation and resource independence
Rainwater harvesting: Collected rainwater can be used for various non-potable purposes, such as irrigation, cleaning, and flushing toilets. If you’re charged individually for water usage, rainwater harvesting can lead to a decrease in your water bills. It helps reduce your family’s demand for municipal water and promotes both water and energy conservation. Rainwater harvesting also reduces stormwater runoff and the associated negative impacts of flooding on downstream water quality in highly urbanized areas.
Low-flow fixtures: Low-flush toilets and low-flow fixtures like faucets and shower heads are designed to reduce the amount of water your household uses, leading to significant water savings over time. This can amount to thousands of litres of water saved each year, contributing to water conservation and lower water bills.
Low-flush toilets typically include single or dual-flush mechanisms, allowing you to choose a lower volume for liquid waste and a higher volume for solid waste, promoting water efficiency. They reduce water consumption by 20 – 60%, depending on use and model. Low flow doesn’t have to mean low pressure and many showerheads provide a similar shower experience while saving 30% on water.
Greywater recycling: Greywater recycling reduces your household’s demand for freshwater, leading to reduced extraction from rivers and aquifers. By reusing greywater, the burden on wastewater treatment plants is reduced, which puts less strain on the infrastructure, with lower energy use and chemical pollution from water treatment. If you end up with a surplus of greywater, its nutrients can benefit your topsoil, with improved soil quality and plant growth when it’s used for irrigation.
If the power grid ever goes down for long, the water eventually stops flowing. With rainwater harvesting, minimizing your water usage and greywater recycling, your needs for fresh potable water will be minimal should you find yourself unable to rely on municipal water. Home water purifiers like Berkey and Alexapure can filter questionable tap water, rainwater, stream and lake water to make them potable.
Designing and building your new home for energy independence is a complex but rewarding endeavour. It will require careful planning, collaboration with professionals, and a commitment to sustainable practices.
By incorporating passive design strategies, a renewable energy system, net metering or energy storage, and efficient appliances, you can create a home that not only meets your immediate needs but also contributes to a more sustainable and resilient future. With advancements in technology and a growing awareness of the environmental impact of traditional energy sources, your journey toward energy independence is both a personal and global responsibility.