Month: December 2020

You can tell the time of the year in a passive solar home by where the light falls into the home (or not) on a sunny day. As the winter solstice approaches, the sun falls into the back of the home, until on the day of the solstice, I designed for it to reach the very back wall of my home.

You can see in the photo here, taken a few weeks ago in the late fall how the sunlight is streaming onto the thermal mass earthen floor, heating the mass. I like living my life close to the planet, connected to its patterns. Its the way humans have lived for thousands of years, like my ancestors in the British isles, the ancient pueblo cultures of the American southwest and multiple other places around the world – we know they lived with this awareness because they built their homes and other structures to mark solstices and to take advantage of this resource that is freely offered by our sun and the positioning of our planet.

Passive solar design and orientation of a home doesn’t provide all of its heat in my climate at 50 degrees north here in southern BC, Canada, but it does provide a considerable portion. Most of the rest of my heat is provided by a deep foundation thermal storage system connected to the active solar heating panels mounted on the roof. The engineer’s calculations estimated that the wood I use for top-up winter heat would be needed for only about 20% of the home’s heat. To put that into perspective, most conventional homes in the area use about a pickup truck’s worth of wood per month, for about 6 months of the year. I so far have used only 2 pickup truck loads per year. I also typically start burning wood a month later in the fall than my neighbours and stop burning a month earlier than them in the spring. (Note: Ideally the home’s top-up heat would be electric, but because I live rurally, use such a small amount of wood, have a good local supply of standing deadwood for wood and the grid here is often down, I chose wood combustion for this home).

Similarly, passive solar design provides a proportion of cooling in the opposite time of the year. As summer progresses, the wide eaves on the home shade and keep the sun from entering. Carefully placed efficient windows yield light but not heat in the summer months. The thickly insulated straw bale walls provide insulation. Along with careful manual window opening and closing, efficient windows, carefully sized and placed provide low-tech, simple temperature control. The house is cooled at night with outdoor air by opening windows sited to gather the almost-always-present valley winds and closing them at day to prevent heat gain. This is all that is required to keep the home cool, even in the traditionally hot summers of this semi-arid region of BC where days can sometimes reach up to 40C.

Why aren’t more homes built this way? Well, that’s why I am writing this, hoping to increase awareness. We also need both land use planning and building code improvements based on local and regional resources, to encourage and require it. The BC Step code is ‘stepping’ in the right direction. But much more could be done. In urban areas, land use planning could take into better account access to the solar resource, both for passive design and for solar electricity access, things that future community designs will ideally be planned around, creating better access for all buildings.

Land use plans need to strategically take advantage of local topography, so that buildings (and food gardens) can access the sun. Buildings need to be able to align their axis east-west as needed and be protected from shading by adjacent structures. We can use east and west slope roofs to gather the solar resource for electricity and heat, but significantly more is gained from direct south exposure. East and West windows require planning to mitigate potential overheating. Ideally all structures built now and in future should have their alignment designed to take full advantage of this resource, for electricity and heating and also for home comfort and light. These things, along with efficient design strategies and materials, can make our building stock part of the many solutions for Climate Change.~

Published in Interior Wellness Magazine, Fall 2014.

“In Canada, buildings are responsible for: 33 percent of all energy used; 50 percent of natural resources consumed; 12 percent of non-industrial water used; 25 percent of landfill waste generated; 10 percent of airborne particulates produced; and 35 percent of greenhouse gases emitted.” (Green Building in North America: Opportunities and Challenges. Secretariat for Commission on Environmental Co-operation. 2008.)

Use Less of the Planet
A building’s energy consumption will exist for its lifetime according to its design and its occupants’ habits. There is also the energy cost of the materials that go into the creation of the building and the fuels and materials used in the construction event itself. “Embodied energy” is the total of energy inputs used to create and deliver a product or service and it is a valuable way to consider how we build. Make it count.

Create a Healthy Home
Many typical construction products off-gas toxic materials. The Living Building Challenge’s (LBC) Red List and the Leadership in Energy and Environmental Design (LEED) green building rating standards assist us in choosing healthier products for our buildings

Design to Use Less
In terms of energy-use standards, several rating systems exist. Many of you are familiar with LEED, which several buildings in Kamloops meet. There is also Passivhaus, a European standard of overall efficiency which many homes in North America have now met. There are also the distinctions of being Net Zero – this may be Net Zero Electricity or Net Zero [total] Energy. The Energy Star program also rates buildings as well as appliances and products for efficiency.

Design to Provide More
Both LEED and the LBC incorporate multiple standards of sustainability, attempting to encourage not only more efficient design, but healthier buildings and healthier communities. It is possible to create net positive effects on inhabitants, environment and community with our buildings.

What Can I Do?
You don’t need to be building to a rating standard to make use of them. Read about these standards, look at what they value and at how different designers and builders have met their requirements in different ways. On your next project ask your contractors and suppliers questions about what they provide and how they can design for efficiency, use less, create less waste, employ healthier designs/products and include or plan for solar electricity and hot water. Consider the embodied energy in your products. Purchase cleaner and more local materials where possible. Ask for Energy Star, LEED-approved and LBC Red-list free products; they are often available but may not be on display. By making informed changes, however small, we offer others a base of information and drive the shift to a healthier, more resilient, economically and socially healthy, sustainable community. ~

Originally published in Interior Wellness Magazine, Summer 2014.

Solar electricity, or PV (short for photovoltaics) is a viable renewable energy source for Kamloops and the BC Interior here and now!

Our solar resource in Kamloops is greater than many other parts of Canada and Europe. Solar PV prices have now dropped to a level that payback for a system can be realized in 10 to 15 years depending on system size, southern exposure and utility price increases. Both major utility companies have adopted a two-tiered rate schedule and price increases that have long been held back, have started. It now makes financial sense to include or plan for solar in all your renovation and building plans.

Isn’t renewable energy too intermittent to provide large-scale Grid power?

Actually, no. Europeans and Americans have successfully turned to renewable energy despite having more technical challenges to do so than BC. In Europe and California, outgoing power from fossil- and nuclear fuel plants must be adjusted to allow for the variable input of renewable energy sources, unlike BC where our large hydro dam system gives us more flexibility. The patterns of our water levels and high resource times from renewables sync well, aiding this integration. [Also, we now have a rapidly growing battery market that will continue to make integration easier].

To see the impact of solar and other renewable-generated power, we can look at the US and Europe. In 2012, PV generated approximately 5.3 percent of Germany’s total net power consumed. PV and all other renewable energy combined in Germany in 2012 provided almost 29 percent of total net power consumed. Last November, Denmark reached a daily high of 122% of its power being provided by wind energy. Germany had a high of wind power as well the same day and yet their integrated grid functioned well. Record amounts of renewable energy continue to be made each year in both countries. In California this March, PV hit several highs of providing up to 18 percent of daily demand. [Of course, these numbers are all higher now, as the affordability of renewables worldwide has only come down since this writing and uptake has continued to increase. More on this in another blog entry!]

The benefits to building more solar PV into the provincial power grid go far beyond the financial. Installing residential and commercial-scale grid-tied PV and other renewable energy generation helps our community by creating local economic development, enhancing security and building long term societal benefits. It helps the environment, displacing coal and gas generation and causing less need for new hydro development. It helps the utility, creating increased generation capacity, resiliency against peak demand and can yield savings in transmission and distribution costs.

BC currently enjoys one of North America’s lowest rates for electricity and this partly explains why we have not seen more widespread use of PV. But Grid Parity is here, now. Do the math and consider – does your granite countertop or other esthetic item give you a better return on investment while at the same time help save the planet? PV does both, even now at current utility rates.

As part of a continent-wide grid, the more we green our grid, the more we assist other jurisdictions to green theirs by selling them our greener power. Our grid is already one of the greenest in the world. By adding grid-tied solar and other renewable energy, it becomes potentially the greenest and resilient in the world.~

This article was initially published in Interior Wellness magazine’s Spring 2014 issue (pg 17). It is still relevant; many people are still learning about how renewable energy systems work.

Do you know the difference between the types of renewable energy systems?

In the renewable energy business, we often refer to “on-grid” or off-grid”. These terms refer to whether or not the site receives power from a utility. If your home, cottage or business is supplied with electricity supplied by BC Hydro, Fortis BC or another utility, it is “on-grid”.

A renewable energy system can be one of 3 general types

“Off-grid”, a stand-alone power system using a sun, wind and/or water source plus batteries and fossil-fueled generator.

“On-grid”, feeding the energy it provides to your home and as well as back into the utility grid.

“On-grid with battery and/or generator back-up”, which feeds into the grid but has the added capability to supply back-up power if the grid goes down.

We can also create community power systems that can be “off-grid” and can form their own independent ‘micro’ grid supplying multiple homes or businesses.

Shouldn’t we get off the grid?
Many people want to “get off the grid” and think that this will help the environment. What they may not realize is that to be off-grid, they [almost always unless they have an exceptional combination of natural resources] must have a battery bank and fueled generator to maintain their batteries and provide back-up power. Batteries, while recyclable, are energy intensive to produce and currently form a significant portion of the investment in an off grid power system. Fuel also costs money and the environment.

The Value of being Grid-tied:
In other parts of the world, where the utility is coal-fired, one could argue for the green value of going off-grid, but here in BC, while we can choose to do that for independence or due to high utility interconnection costs, it cannot provide a smaller carbon footprint. Off-grid systems are also unable to take advantage of all the energy produced at peak resource times. If you are grid-tied, all the power that you harvest from your renewable source is fed back into the utility grid, wasting none of it. If you have the ability to be grid-tied, this would be your first choice for both financial and environmental reasons.

More to explain the value of being grid-tied, consider overall efficiency and economy of scale. BC has an amazing asset in its legacy of large dams that form the main source of electricity for our grid. They provide us with a storage system for energy that has a low environmental cost. These dams can act as a large battery bank that interacts almost seamlessly with solar and wind power. Integrated into the grid, the electricity that we get from solar and wind, which is intermittent, allows us to draw down our dammed water less, effectively ‘storing’ that energy, creating a more resilient grid. It is a personal choice to be off-grid, depending on one’s desire for independence, the costs of utility interconnection, utility dependability, lifestyle and personal preference. The choice to be off-grid is not ‘bad’ for the environment, but should be made with an understanding of the factors involved. ~