Paying for power for the first time since summer

An update on our home’s solar power system

If you’re a longstanding subscriber, you probably know that I’m a big fan of solar panels to generate emission-free electricity and save money.  You may also know that we’ve had solar here at home for the past few years.  Here’s an update.

First, a quick backgrounder:

• In late 2020, we installed our first solar system, consisting of a ground-mount (IE a rack in our yard) with 6 KW of solar panels plus a battery backup system
• Our array is grid-tied, so we’re still connected to NB Power. Anytime our solar panels are producing more power than we use, the surplus automatically gets sent out NB Power’s lines; and we automatically get power back from NB Power anytime we’re using more than the panels are producing (like at night).
• Our system is net-metered, meaning that our power meter keeps track of any surplus power we send out the line, building up a credit we can draw back anytime we need more power than our panels are providing.
• The system’s battery backup automatically takes over during power failures, with barely a flicker of our lights (my favourite feature).

Results from that first array:

• In its first two years of operation, our solar system provided about two-thirds of the power we used to run our home and charge our EV. 
• Equally important, it has seamlessly provided us with backup electricity through several power failures – including through the two-day outage we experienced after a hurricane-like storm blew through NB December 18.

Because our system has worked out so well, we added a second array of panels last June – this one on our garage roof – with the hope that the two systems combined will take us to net-zero on an annualized basis.

Results from the combined arrays:

• Since the second system was installed in June, the two arrays have generated more than we have used, building up a credit with NB Power.
• That credit has carried us through the fall to the end of December (as shown in the graphic below, snipped from our last power bill).

Alas, this month we’ll be using up the last of the credit and then paying for purchased electricity again – but for the first time since June, which isn’t too bad.

The good news: solar panels actually love cool temperatures, so on bright days like yesterday, our original array, pictured above, produced a near-perfect ‘bell curve’ of power, and had us into surplus territory for a good part of the day.

More good news: the federal government offers great incentives for the installation of solar systems, as do most provinces; NB’s programs are here.

If you haven’t looked into solar yet, you owe it to yourself – for cost and emissions savings (resilience and self-sufficiency too)!

One last point: I’m tentatively planning another Open House this spring, date to be confirmed, for anyone who’d like to see a solar system up close.  If you’re interested, please just hit reply to let me know, or click on the icons below to find me on social media.

Suggestions from a reader!

Thanks to subscriber Grace Beazley for sharing the following additions to December 27^th’s Make 2024 your “Sustainability Big Year” action list:

• Reduce the length of my shower to __ minutes
• Use cold water for washing my clothes
• Buy my laundry soap at stores where I can refill my reusable containers

Heat Pumps 101

A closer look at one of the best ways to save AND reduce emissions

Heating accounts for about 60% of the energy used in Canadian homes and buildings.  It’s expensive, and it can be a huge source of emissions too, especially if that energy comes from natural gas or coal-fired electricity.

Heat pumps to the rescue!  They’re super efficient – and current incentive programs make them really affordable too.  Plus – the International Energy Agency estimates that widespread adoption by 2030 could reduce global greenhouse gas emissions by at least 500 million tonnes a year – that’s equal to the annual emissions of all cars in Europe today!

So here, in point form, is a short primer about heat pumps.

• How they work: it’s helpful to imagine buildings with heat pumps as inside-out refrigerators.  Whereas a fridge is a box where the inside gets cooled and heat is expelled out through the coils on the back of the box, a building with a heat pump is a box where the outside gets cooled, and heat is expelled into interior spaces. 
• There are two types: air-source heat pumps extract heat from outside air by cooling it several degrees.  They then release that heat into interior spaces.  Ground-source heat pumps (also called geothermal heat pumps) use wells or a system of underground coils to extract heat from underground in the same way; and then release that heat into interior spaces.  Some also produce hot water.
• Air-source heat pumps can be ductless or ducted: ductless heat pumps (also known as mini-splits) have their indoor units mounted on a wall and release heat directly into the room in which they are located.  Ducted heat pumps (also called central heat pumps) distribute heat throughout a building via a system of ducts.
• Super efficient: whereas baseboard heaters produce just one unit of heat for every unit of electricity used, heat pumps can produce up to five units of heat for every unit of electricity used.  That explains why they can be such money-savers!  (The fine print: keep reading for more on cold temperature performance of air source heat pumps.)
• Operating range: today’s air-source heat pumps work well to temperatures as low as -25 degrees C; some even work to as low as -30 degrees C.  However, it’s important to note that their efficiency does drop the colder it gets (because the colder air is, the harder it is to extract heat from it).  Ground-source heat pumps are consistently very efficient all year round because temperatures underground are very stable.
• Advantages of air-source heat pumps: less expensive to install than ground-source; ductless in particular are easy and inexpensive retrofits for homes and buildings with baseboard heaters.
• Advantages of ground-source heat pumps: very efficient year-round; able to provide domestic hot water as well for further savings.
• Some maintenance required: all heat pumps require basic maintenance like regular cleaning of filters, and perhaps annual servicing by a qualified contractor.
• Cooling, a double-edged sword: most heat pumps have the ability to provide cooling as well as heating.  The downside: summer air conditioning may offset some of winter heat savings.
• Incentives: check out generous federal incentives under the Canada Greener Homes Initiative, the federal Oil to Heat Pump Affordability Program and for your province (for New Brunswick, here).

For a deeper dive, check out this guide from Natural Resources Canada, or this explanation complete with cool graphics!