FAQ

General FAQ

 

What is the Warranty on the Solar Power System?

Solar panels have a manufacturer’s warranty of 25 years.  SolarEdge optimizers also have a 25 year warranty and the SolarEdge inverter has a 12 year warranty, extendable to 25 years.  Micro-inverter warranties vary, depending on manufacturer.  Suncatcher Solar has a 5 year installation warranty and provides free installation of warranty replacements.

What is the expected lifetime?

The expected lifetime is 35 or more years.  Solar panels already exist that have been producing for longer.

If I have to replace my roofing, what would you recommend?

Metal roofing or asphalt shingles with a 35-year warranty both have a long lifetime.  A light color will keep the house cooler in the summer and light colored shingles also last longer.

Will solar panels be damaged by hail?

Solar panels are mounted in aluminum frames with tempered glass faces.  They are very robust and would only be damaged by extremely severe hail storms,  See a hail test in this Tips article:  Solar Panels and Hail.  In this case, the panels should be covered by your home insurance policy.  Contact your insurance provider for details.

What happens in winter?

Solar energy varies throughout the year.  Typically, the average roof angle combined with the short days of winter makes production low in the winter but optimal during the summer. Snow cover typically slides off or melts off once the sun shines again.  Net metering takes advantage of the high summer production to offset the much lower production in the winter.

 

Grid-Tied Systems

 

What does the Rebate include?

The rebate applies to the equipment, installation and design costs for a solar power system that   is connected to the electrical utility company.  The rebate, to a maximum of $20,000, is  available for customers of SaskPower, Saskatoon Light and Power and the City of Swift Current.

What happens during a power outage?

During a power outage, your solar power system will not continue to produce. Your system must shut down automatically so that the problems with the electrical utility system can be safely repaired.  When utility power is restored, your solar system will automatically restart and again produce power for your home.

What are the options for backup power?

If you have critical loads or frequent power outages, battery backup can be added to your grid-tied system or you can use a backup generator.  Costs vary depending on how much backup you want.

How do I read the bilateral meter?

Solar Saskatchewan Meter - received from customer

rEC – Received from you and credited to your account

When your solar power system starts producing, a bilateral meter will be installed to replace your regular meter.  This will record the excess power you feed back so that your account can be credited.  Reading the bilateral meter can be confusing.

The bilateral meter has 3 rotating displays.  Display 1 is a series of ‘8′s.  Display 2 is ‘dEL’ followed by the number of kWh that SaskPower has delivered to you.  Display 3 is ‘rEC’ and the number of kWh that SaskPower has received from you for your excess solar production.  This number will be credited on your utility bill at the current rate.

Get a Quote for a Grid-tied Solar Power System:

Call toll free: 1-877-441-2355 or email

Plugging it in: From Off-Grid to Grid-tied

In 2003 I decided to follow a long time dream to build a solar home.  On an acreage near Saskatoon, I designed and built, with my husband, a passive solar home with an off-grid solar and wind power system.

Our Solar Home Experiment in 2003

Solar Saskatchewan Our Home Exterior 2004We chose to do an off-grid system because, in those days, there were no good programs to feed power back to the utility and no incentives for installing grid-tied solar.  In Saskatchewan, the solar industry was still very young and solar power was still quite expensive.  Our home, built as a modest 24′ x 28′ ready to move (RTM) home, was our experiment in passive solar design and off-grid power.

Solar Saskatchewan our kitchen

 

 

 

 

 

 

Our solar and wind power system supplied the 5 kWh per day that we needed for our energy efficient home. An inverter converted the DC power from our solar and wind power to the normal AC power required for all the standard appliances in our home. A large battery bank stored power for overnight and cloudy days, providing backup for at least 3 days of very low power input. We used a backup generator for the short days of winter when there were long periods without enough sun and wind to keep the batteries charged. Winters can be a bit of challenge in an off-grid house.

Our Solar Home Experiment in 2016

After 13 years of off-grid living, we decided to convert from Off-grid to Grid-tied Solar. Why?

1. Seasonal Storage

Many a summer morning our batteries were full by 10:00 am. With nowhere else to store any excess sun power coming in, whatever we didn’t immediately use for our house after 10:00 would be wasted. What a shame!  If only we could store that for the winter!  A grid-tied system on the net metering program makes that possible. Our excess solar power in the summer is now fed back to SaskPower for credit for the winter months, at the same rate that we are paying.

2. SaskPower becomes our backup

Instead of starting the generator when there is not enough solar power to keep the batteries charged, SaskPower now provides that backup. For us, this means that we no longer need our backup generator with its maintenance and fuel requirements – and noise! Generators also have a much shorter lifetime than a solar power system.  It had become time to replace our current generator, an expense that was roughly equivalent in cost to bringing in grid power.  We chose grid power – SaskPower is a much less expensive and more convenient backup than a generator.

3. Battery lifetime will be much longer 

Battery lifetime depends on how often you cycle the battery, which happens every time you have to use power from it to run your household.  With the batteries constantly being charged due to our grid-tie connection, the batteries are only cycled during a power outage when they become our backup.

During a power outage, a grid-tied system must shut down automatically so that the problems with the electrical utility system can be safely repaired.  However, if you have a backup battery bank like ours, you can switch to this backup during a power outage.  Since this does not happen often the typical battery life of 10 – 12 years will be substantially extended.  This is a big advantage since a battery bank like ours is around $10,000 to $12,000.  We have already replaced our battery bank once. 

4. Electric appliances replace propane 

We replaced our propane appliances with electric appliances because their energy usage can be offset by solar.  It also reduced our reliance on propane deliveries and fluctuating prices. To compensate for the new electric appliances – cookstove, water heater and space heater – we installed more solar panels.

What do we miss from being Off-Grid?

We miss the sense of pride in being self sufficient, which is what attracts many people to the idea of living off-grid. We also had a very clear idea of what we were using for power all the time, which was shown on a battery system monitoring display. When we started the toaster, or the water pump started up, you could see the sudden power draw from the batteries on the monitor. Once we became grid-tied this display became meaningless. Our batteries are constantly fully charged from grid power (except during a power outage).

Off-Grid Systems:  Ideal for Remote Homes or Cottages

Off-grid systems can provide reliable power where utility power is not available or is very expensive to bring in. The system must be sized appropriately to meet your needs and being energy efficient is important to keep costs down. New off-grid inverters provide internet monitoring for the system and are Grid-tie ready if it becomes more feasible to connect to the utility.

Living in an Off-Grid Solar House – The Good, the Bad, and the Ugly

I built my off-grid solar home with my husband in 2003. The house was originally powered by a combination of solar and wind power. Living off-grid is an interesting experience.  Everything you do – cook lunch, have a shower, watch TV – it’s all powered by the sun or the wind. A pretty cool feeling – most of the time. Let me introduce you to the GOOD, the BAD and the UGLY.

We experienced them all one January in 2006. January 23 was clear and cold. A bitter wind raged through the bare trees and whipped the snow into eddies and drifts.  But for us, it was still a good day because the sunshine and horrendous winds gave us a record day for power. Not all days are like that.

This is what that a good day looks like to us:

A Good Day for Solar and Wind Power

A Good Day for Solar and Wind Power

You can see the sun rise in the first chart, see it start to produce more and more power until solar noon, then decrease again till sunset – a nice uniform curve. The jagged dips are from wisps of cloud crossing the face of the sun. The second chart shows the wind power – it is recorded in short intervals and what you see here in red is the maximum and minimum power for each interval, with a line in the middle for the average. You can see how variable the wind is, compared to the solar – it’s not the steady line or curve that you might expect.

That night the wind started to die down and the next day started out cloudy, with some clear sky later in the day.

A Bad Day for Solar and Wind

A Bad Day for Solar and Wind

But this is not the worst it can get. Imagine a day with no wind and it’s snowing. Here it is – the UGLY day.

An Ugly Day for Solar and Wind

An Ugly Day for Solar and Wind

Fortunately, we don’t see many days like this – but notice, there is still some solar power, even when it’s snowing.  It is for days like this that an off-grid system has a large battery bank to see you through. In January, however, that may not be enough to carry you through all the bad and ugly days so a backup generator is also part of the system.

This is what the whole month of January can look like (2006 had an unusually cloudy January).

Our Solar and Wind Power for January 2006

Our Solar and Wind Power for January 2006

The yellow bars show the solar power we received, and the blue bars represent the wind power. Add the two together and you have the total power. You can see January 23, the GOOD day, as a very tall bar – we produced 12 kWh of power that day. We only need 5 kWh a day to run our house so we stored the extra in our batteries. The next day was the BAD day – you can see how short that bar is in the chart. The UGLY day was January 13 – a very short bar indeed.

This was the worst month of the year. Most months there is plenty of sun and wind to supply all the needs of our home. That is the story with off-grid homes – you can store power for a few days, but there is no way to store all the extra power from the summer for months like this. That is the big difference between off-grid and grid-tied systems. Grid-tied systems are connected to the utility grid and, where net metering is offered, you can use the utility grid to “store” excess power that you produce in the summer for the winter months. This is done by giving you credits on your bills for the extra power.

As I am writing this, we are having one of those ugly days. Our wind turbine is not turning and we are having our first snowfall of the season. But it’s been a long and beautiful summer and fall. Like farmers, we have to work with the vagaries of the weather, but we enjoy the rewards of being self sufficient, environmentally friendly and never having a power outage.

 

What is the Best Tilt Angle for Your Solar Array?

To get the most out of your solar panels, your solar array needs to be angled appropriately to get the most direct sunlight, for as much of the day, as possible. So how can you generate the most electricity from your array? In a nutshell, face the solar array:

  1. as close as possible to true south (not magnetic south)
  2. towards an area where nothing will shade it
  3. perpendicular to the sun’s rays.

The first two depend on the space that you have available. The third depends on your location on the globe, and that is the topic of this post.

The amount of electricity that a panel produces depends on the amount of sunlight reaching the panel. As you would expect, the panel receives the most sunlight when the sun’s rays are striking the surface directly – at ninety degrees to the panel. A simple enough idea, if only the sun would stay conveniently in one place!

Since the sun is constantly moving across our skies, you either need to mount the panels so that they track the sun, or you need to find a compromise that still gets good solar production. Solar trackers, although they sound like the perfect solution, take up space in your yard and are more expensive than buying a larger solar array to compensate for the lower production of a fixed mount.

Optimizing a fixed mount solar array means looking at both daily and seasonal variations in the path of the sun.

Tilting Your Array for Seasonal Changes

Monthly Sun HoursUnless you live near the equator, the sun’s position above the horizon will change from summer to winter. In the summer, when your part of the world is tilted towards the sun, you will see the sun rise in the northeast, then move high up across the southern part of the sky to set again in the northwest. Come wintertime, the sun rises in the southeast and barely seems to get above the southern horizon before it sets again – all too soon – in the southwest. The further north you are, the greater is the difference between the winter and summer sun paths.

What is the best fixed angle for these seasonal variations? Let’s take a look at an example home site in central Saskatchewan at latitude 52 degrees north. There is plenty of climate data available that will show you how much sunshine you will get at a particular latitude and solar panel tilt angle.

Looking at the bar graph of average annual sunshine hours for various tilt angles, you can see that a good compromise is to tilt your array somewhere between 37 and 60 degrees. These angles receive almost as much sunshine as changing your array every month to set it for the optimum angle for that time of year.

Another interesting graph of sunshine hours over the course of the year for several different tilt angles shows that the biggest difference is in the summer.

Monthly Sun HoursDuring the dead of winter, there is very little difference between the various angles.  This means that if you are on a net metering system where you can store your excess energy from the summer for use in the winter you are better off with a lower angle that gives you better yearly production.

So the bottom line is that there is not a huge difference in production between angles from 35 to 65 degrees. This means that if you have an unshaded south facing roof space at an angle somewhere in this range, a roof mounted array is the most cost effective choice for you.

Solar Array Angle for the Sun’s Daily Path

The sun’s path across the sky during the course of the day presents a much bigger challenge for keeping your panels pointed directly at the sun. Having ruled out a tracker for most applications, what’s the best way to set up your fixed array?

Daily Solar Power

Daily Solar Power

The sun is at its brightest at noon and at due south. If you face your array to the south you will capture the noon sun and also a large proportion of the morning and afternoon sun. If your array is facing more to the east you will lose some of the key noon hour advantage and some of the afternoon sun.  Similarly, pointing the array more to the west will lose some of the morning sun and some of the noon hour production maximum.

Homes with roofs facing east-west are still good choices for roof mounted arrays if enough south facing roof space is not available.  If you have a standard 4/12 roof pitch your panels will be angled at about 20 degrees and will still capture much of the solar production throughout the day.  An east or west facing array at this angle will still produce about 80% of the production of an array on a south facing roof at the same tilt angle. Steeper east or west facing roofs will lose a little more of the production.

Now you can have a look at solar mounting options to see which one will give you the best angle on your property.

Calculate Your Carbon Footprint

Have you wondered about your own carbon footprint? We found this calculator to help you work it out. Collecting all the information you need may be an interesting and illuminating exercise on its own.

How to Calculate your Energy Load

The size of the solar power system you need depends on how much energy you use. The first step in designing a solar power system for your house is to figure out how much power you need to run the various systems and appliances.

 

Types of Loads

 

Loads can be continuous (running 24 hours a day), or intermittent. Many loads – such as a refrigerator, toaster, or vacuum cleaner – use a large amount of power but only for short periods. The best way to figure out how much power your appliances need is to measure them with a power usage meter (the Kill A Watt meter is one example).

Often, something that draws little power (such a standard light bulb at 60 watts) will use more power per day if left on all day than a very large intermittent load such as a coffee maker drawing 900 watts for 20 minutes. For example:

  • A 60W light bulb, 60W x 24 hrs = 1440 Whr.
  • A coffee maker uses 900W x 1/3 hr = 300 Whr.

It is also evident from this example that if you use energy efficient compact fluorescent light bulbs, which produce the equivalent of a 60W light bulb but consume only 13W, this bulb would use only 312 Whr in a day even if you left it on all day.

There are some loads that are not obvious and are easily overlooked when calculating load requirements.
  • The inverter will draw a certain minimum amount of power.
  • Anything that has a remote control (like the TV or stereo) draws some power at all times so that the remote will be ready to turn it on at anytime.
  • Computers may also draw power even when they are not turned on.

These types of loads are called “phantom loads” because they are not readily apparent. They draw only a small amount of power. But even a small amount of power, if it is continuous for 24 hours a day, can really add up. These loads can be mostly eliminated by installing a switch, or a switched power bar, that turns off the appliances when not in use.

Once you know the energy loads you’re using, the total amount of energy that you use and what the solar array will have to supply, can be calculated.

 

Calculating Your Total Load

 

Multiply the power used by each appliance times the hours per day that you use it – this gives you the total number of kWh per day for that appliance.

Add up all the appliances and you will have the total number of kWh that you need per day.

Adjust the total number for the efficiency of the inverter, typically 90%.

Definitions:

  • Power is given in watts (W) – a thousand watts is a kilowatt (kW).
  • If you use a kW of power for one hour this is a kilowatthour (kWH). When you look at your utility bill you will see that the power you have used over the month is listed as some number of kWH.
If you use a spreadsheet program you can easily change the hours/day or the power draw of different appliances to find something that will work best for you.

 

An Example Load Calculation used for the Suncatcher Solar Prototype House
Load Rated Power (W) Hrs/day kWh/day
Mechanical:
Water pump 1200 0.3 0.36
Septic pump 800 0.05 0.04
Kitchen Appliances:
Fridge 404 kWh/yr As rated 1.10
Coffee Maker 900 0.25 0.23
Toaster 900 0.2 0.18
Toaster Oven 1300 0.1 0.13
Electric Frying pan 1200 0.02 0.024
Slow Cooker 110 .1 0.011
Lighting and fans:
10 lights @ 15 Watts 150 2 0.3
Ceiling fans (2 @ 12W ea.) 24 4 0.1
Office and Entertainment:
Television (27”) 100 2 0.1
VCR 30 0.5 0.015
DVD Player 30 1 0.03
Radio 2 15 0.03
Stereo 20 2 0.04
Aquarium lights 45 3 0.14
Aquarium filters 20 24 0.48
Laptop Computer 50 6 0.3
Printer 10 1 0.01
Modem and wireless router 40 4 0.16
Laundry:
Washer (front loading) – see Note 1 227 kWh/yr 0.5 * rated 0.3 1
Dryer (110 V) – see Note 2 398 kWh/yr 0.1 * rated 0.1 2
Iron 1100 .05 0.05
Small Power Tools 600 .1 .06
Car Block Heater 1200 .01 .01
Battery chargers 6 2 .01
(tools, cell phones, camera, etc.)
Total AC Load: 4.31
@ 90 % inverter efficiency: 4.74

Notes:

  1. The energy rating in KWh/year is based on 416 “Normal Cycle” operations per year and includes the energy required to heat the water. This is more than one load per day, which is not necessary for two people. The usage estimate has been adjusted accordingly.
  2. This energy rating in KWh/year is also based on 416 operations per year. Our usage would be less based on fewer loads through the washer and we often hang the clothes to dry. Again, usage has been adjusted accordingly.

Keeping Pests and Debris away from your Solar Panels

A Problem with Pests

As it turns out, pigeons and squirrels love to nest under roof-mounted solar arrays. Squirrels, in particular, can do serious damage to the wires hooking up your inverters to your solar panels. These damaged wires then become a fire hazard. The detritus from nests (as well as dried leaves that can accumulate under panels) can cause damage to your roof and lead to roof rot. Beyond all the mess and the hazards, there is the issue of noise that pigeons cause. All that to say, unprotected arrays can cause you serious problems and headaches.

Prevention

Because of the fire hazard caused by damaged wires of string inverters*, it is now code that all systems using string inverters must have some kind of protection around the panels to keep pests out. For our solution to this problem, we use a beautifully designed aluminum trim created by SolaTrim.  SolaTrim has several advantages over a simple wire mesh. It is a strong product made of lightweight aluminum with an aviation grade adhesive tape that seals it thoroughly to your solar panels. It is extreme temperature tested and comes with a 25 year warranty. We like that it is designed to be a permanent solution that will last the lifetime of the panels. We also chose this solution because we wanted to use a trim that didn’t detract from the beauty of your home. SolaTrim adds curb appeal to your house by providing a clean and elegant finish to the array.

Suncatcher Solar System on Triangular Roof

Roof-mounted solar Array with SolaTrim around the panels to keep out debris and pests.

*Systems using either SolarEdge or Micro Inverters are designed to shut down automatically if there is damage to the wires. For this reason they don’t present a fire hazard, and installers are not required by code to install any sort of mesh protection. However, we always install trim, regardless of the type of inverter, to avoid the noise and protect your system and your roof.

 

Gardenview Solar Home

The Gardenview solar home is an example of  a passive solar home that fits on a city lot.  It was designed by Suncatcher Solar and built in partnership with Jaylin Homes in Saskatoon, Saskatchewan.

It features energy efficient building construction, radiant in floor heating and a solar power system.

Passive Solar Design

Living room in late October

Living room in late October

The south side of the completed home, shown here, faces the back yard, where the owners are planning a large garden.  Normally the south wall is the long wall of the house but the shape of the house was constrained by the size of the lot.  Despite these limitations, however,  the home’s south windows are 9%  of total floor area.

Stone facing stores the winter sun's heat

Stone facing stores the winter sun’s heat

Abundant sunshine into the house warms the home during the winter.  The roof overhangs keep the sun out in the summer, when the sun is higher in the sky, so that the house stays cool.  Thus, a passive solar home typically does not need air conditioning in the summer.  Stone facing on the fireplace and a granite countertop act as a thermal mass to store the winter sun’s heat for overnight.

Wiinter and Summer

Wiinter and Summer

North side of Gardenview home

North side of Gardenview home

The attached garage is on the north side of the home, with the bedrooms above.  Fewer windows are needed here, increasing the energy efficiency of the home.

Energy Efficiency Features

The bitter cold winters in Saskatoon, plunging to temperatures as low as 40 degrees below zero, make energy efficient building methods an important component of the passive solar design.

Upper floor landing

Upper floor landing

The Gardenview is built with wood frame construction with 2″ x 6″ walls and blown-in insulation.  Themal bridging – heat lost through the wooden framing members – is a major source of heat loss in this type of construction.  The Gardenview reduces this heat loss with 1″ foam board insulation applied to the inside of the exterior walls.  The inside of the foam board is faced with a reflective foil to reflect heat back into the home, cutting down on heat loss through radiation.  An air gap between the foil and the drywall is essential to make this method effective and can cut down on radiation losses.

Heating System

A woodburning fireplace provides renewable heat

A woodburning fireplace provides renewable heat

Radiant in floor heating on all levels of the home supplements the passive solar heating.   The attached garage also includes in floor piping, but the temperature is kept considerably cooler than the house.  A wood burning fireplace provides extra heat and ambience on cool evenings.

The in floor heating is supplied by a Wiessman natural gas modulating boiler.  The system uses a sophisticated central controller to program the heat requirements of the home.  The in floor system has a continuous flow and is automatically adjusted based on the reading from an outside temperature sensor.  When the outside temperature goes down one degree the temperature of the in floor system is increased by 0.7 degrees or whatever the controller is programmed to.  This can be adjusted to suit the preferences of the occupants.  A fine tune control knob lets the homeowner make minor adjustments as needed.  The advantage of this sytem is that, once it is set, it usually does not need to be adjusted often and the continuous flow means that the boiler can operate at a lower level (typically 25% of its maximum output), thus saving energy.

Bruce explains the in floor heating system to the homeowners

Bruce explains the in floor heating system to the homeowners

The system was designed and installed by Bruce Kell of Solaero Energy.  When he was going through the system with the new owners he commented that at a previous installation the natural gas utility had come and changed their meter because they thought it wasn’t working properly.  But it was – that’s just how energy efficient this system is.

Solar Power

A solar power system provides renewable electricity

A solar power system provides renewable electricity

The homeowners were very excited when the day came to commission the 2.3 kW grid-tied solar power system that will offset some of the home’s electrical usage with clean, renewable power.  The system can be expanded in the future, once they have lived in the home for a few months and have a clearer idea of how much power they will need.  The system qualified for a rebate on the upfront costs and Saskatchewan’s net metering program means that excess power produced over the summer months can be fed back to the electrical utility for credits on future bills.

enphasedisplay

Click here to see the Live Display for the Gardenview

The solar power system features a monitoring system that lets you see – live – exactly what each of your solar panels is producing at any time, as well as your overall production per day, per week, per month and since you installed the system.  The webpage will also show what this means in terms of the environment, showing the greenhouse gases offset by the system.

The solar panels and Enphase inverters have a 25 year warranty and an expected lifetime of over 35 years.

Owners’ Comments

The Gardenview has a bright, sunny kitchen

The Gardenview has a bright, sunny kitchen

After only a few days in their new home, the owners were already amazed by the solar heat coming through their south facing windows.

“The solar gain on sunny days is absolutely incredible – we turn down the fine-tune dial as far as possible in the morning and with opened windows in the afternoon, it’s still 24C on the main floor!”

Their in floor heating settings were tweaked to moderate the heat gain and heating costs have been very moderate for their first winter – under $300 for natural gas during the first year they lived in the home.

For more passive solar home designs see Suncatcher’s Solar Home Designs.  You can also buy a Study Set to have a more detailed look at the plans before deciding to purchase the full set of drawings.  Plans are priced at $995 for the Construction Drawings and $29.95 for the Study Set.

Off-Grid or Grid-Tied – What’s the Difference?

Solar Power Array on the Experimental HouseSolar Power Center“I want to go off-grid and use solar instead of bringing in SaskPower!”

The desire for independance prompts many a call to Suncatcher Solar from people who want to be self sufficient and hope that solar power holds the answer to that dream.  But what does that really mean? What’s the difference between “off-grid” and “grid-tied” and what kind of lifestyle does each one entail?

What Does it Mean to Go Off-Grid?

Going off -grid means going it on your own. You have to produce and store all your own power and if you run out you start up the backup generator. There is no power utility to fall back on. On the other hand, neither is there a power bill.

Basic-Solar-Power-System1-e1318386617230

Off-Grid Solar and Wind Power System

An off-grid system needs a storage system for the electricity that you produce so that it will be available for times when there is no source of electricity. This storage system is one of the main features that distinguish an off-grid system from a grid-tied system. The other is a backup generator for long periods of cloud or calm.

The figure at the right shows the basic components for an off-grid system. A solar array and an optional wind turbine provide electricity to run the appliances in your home. Whatever you don’t need immediately is stored in the battery bank. Since you are completely reliant on your own resources the battery bank must be large enough to see you through at least 3 days without any solar or wind charging. This typically means very large battery cells forming a bank that requires a space that is a minimum of 2′ wide by 4′ long and 3′ high.

Remote Solar Power System

Remote Solar Power System

You will need to plan your energy use using a load analysis so that the charging system and battery bank is large enough to meet your needs. Heating your home in a cold climate will present some challenges. Some heating systems are difficult or prohibitively expensive to operate with an off-grid system. For example, you cannot run a geothermal system with off-grid power – the power requirements for the pumps are too large. Passive solar design and an in floor heating system are usually the best options for off-grid systems.

What is a Grid-tied Solar Power System?

Grid-tied Solar Power System

Grid-tied Solar Power System

A grid-tied system is connected to your electrical utility company’s power “grid”. The utility is now your backup generator. There is a basic monthly cost for a grid connection (usually around $25) but this is much less expensive than the $6000 or more for a generator and the fuel that the generator uses.  You can see the utility meter and subpanel for the large solar array shown in the photo on the right.

Grid-tied Solar Array

Grid-tied Solar Array

A grid-tied system often includes a net metering agreement. This means that when you produce extra power you can feed it back to the grid and receive a credit on your power bills for those times when you use more than you produce. Some utility companies may also pay you for your excess power, or buy power from you at higher than the going rate (this is called a Feed-In Tariff ).

Grid-tied solar power system

Grid-tied Solar and Wind Power System

The grid now also becomes, in a sense, your battery bank. Because you feed back your excess power for a credit, it is effectively “stored” for you until you need it. Usually this means that you feed back extra power in the summer and then use the credits in the winter when you need the power for your heating system. This is much less expensive than buying and maintaining a battery bank.

Looking at the figure on the left you can see that the grid-tied system is the same as the off-grid system but without the battery bank and its charge controller and without the emergency generator.

A Cost Comparison

This means that it is much less expensive to set up and maintain a grid-tied system. It also means that most of your money is going to what you really wanted to buy in the first place – solar and/or wind power. The inverter system, which converts the DC solar power to normal household AC power, is the only other expense for materials. Installation is also less expensive if there is no battery bank, charge controller and generator to install.

This typically makes a residential grid-tied system at least $15,000 less than an off-grid system. So why would you want to invest in an off-grid system?

Off-grid systems are still cost competitive if you live sufficiently far from the closest grid connection. If you need to have power brought in it may cost you at least as much or more to connect to the grid as to pay for the batteries and generator required for an off-grid system. If it will cost you $20,000 or more to bring in power, for example, the off-grid system quickly pays for itself, especially since there will be no ongoing power bills.

A Benefits Comparison

Off-grid System Pros and Cons:

Off-grid Battery Bank

Off-grid Battery Bank

Pros:

– ideal for more remote situations where power is expensive to bring in.
– no power bills.
– no power outages.
– self sufficiency on a clean, renewable energy source.

Cons:

– batteries and generator are expensive and require maintenance.
– lifetime for the batteries and generator(10 – 15 years) is less than for the solar array (35+ years) and wind turbine (20-25 years).
– no seasonal storage. Batteries can only store power for a few days and have a maximum capacity. When they are full, the rest of the power is wasted unless you can find an immediate use for it.
– power use must be carefully planned.

Grid-tied System Pros and Cons:

Pros:

– easy backup from grid power.
– eliminates need for expensive batteries and generator (which also requires fuel).
– provides seasonal storage if a net metering or Feed-in Tariff program is available.
– maintenance free for a solar power system (wind requires some maintenance and repair).
– internet monitoring available with inverters designed to be used for individual solar panels (Example).
– you are providing clean energy to the grid.

Cons:

– power outages. When utility power goes out your system also goes out unless you invest in a battery bank. This is a requirement by the utility company and is for the safety of those repairing the system.
– you still have to pay the basic utility bill, just not for whatever power you’ve produced.
– you are still using non-renewable resources when there is no solar or wind.

Making the Choice

Choosing the power system that’s right for you depends on your building site and the lifestyle that you prefer to live.

Contact us and discuss the options with us.

Choosing Solar Power for Your Home

Girls from a Science Camp check out my solar home

My solar home

live in a solar home – it is powered by the sun.  When I make my morning toast, grab my drink from the fridge, sit at my computer and write this post, it is powered by the sunlight striking the panels  on my roof.

It is an exhilarating and  liberating feeling – I am using solar power, something that is already shining on my home in clean and limitless supply.

If you live in an area with plenty of sunshine, like Saskatchewan, you can make this happen for your home.  This article explains what’s involved in deciding on solar power for your home, farm or business.

Choosing a Location for the Solar Panels

Solar panels work by converting sunlight to electricity – the more sunlight that strikes the panels, the more electricity they produce.  The best position for maximizing the amount of sunlight is facing the equator (true south in the northern hemisphere, true north in the southern hemisphere).  The more panels you have, the more sunlight they will receive and the more electricity they will produce.

House Roof

Solar Power on House Roof

A roof clear of obstructions

Solar panels take space. The most convenient place to put them is on your roof if you have a large enough area facing close to true south (true north in the southern hemisphere).   A typical city home will need about 10 solar panels.  Those 10 panels will require 35 feet by 15 feet of south facing roof space. The roof should be as clear as possible – no vents, antennas or other obstacles that would interfere with mounting the panels or shade the panels. East and west roofs will also work but will need 20% more panels to produce the same amount of electricity.

Outbuildings

If you don’t have room on your roof there are other places to mount panels.  Look at a garage or shed roof – see if these have a clear south facing roof that’s large enough to accommodate the panels.

Pole Mounts and Trackers

Solar Panels on a Pole Mount

A Pole Mount

Solar panels can also be mounted on a pole  – some of these can be adjusted for the seasons.  If you are really short of space and need to make the most of what you have a tracker is another, though expensive, option.  This automatically tracks the sun over the day and the seasons.

Ground Mounts

Solar panels on a Groundmount

A Ground mounted Rack

A simpler, less expensive option than pole mounts is to mount panels on a rack on the ground.   You will need room in your yard for these mounts – they will need to face south and have a clear area in front of them so that there is little or no shading.  Large trees or brush, other buildings or farm structures can shade the panels if they are too close.

Getting the Most from your Solar Investment

Solar panels will produce the most power if they are set at the optimum angle and orientation for your geographic location, and in an area with no shading.  This ideal position may not be practical for your roof or yard but very good power production can often still be achieved with the apace you have available.

Minimize Shading on the Solar Panels

If you plan to mount the panels on your roof, look to see if you have chimneys or gabled dormers that would shade the panels at some times of day.  Snow can also build up beside dormers covering any solar panels that are mounted close to them.

Other sources of shading are tall trees in yours or your neighbor’s yard and any outbuildings on your own or neighboring properties.  The key is to find the least shaded area in which to mount your solar array.

What About Snow Buildup?

If you get lots of snow in the winter, you will want to do something to avoid snow buildup on the panels or have an easy way to remove the snow.  A steeper roof angle will help because the snow will slide off more quickly when the sun comes out and warms the glass surface of the panels.  As the surface becomes slippery the snow will slide off fairly readily.

If your roof is not too high up you can use a roof rake on an extended pole to remove the snow from the panels on those few occasions when it will be needed.

Some Other Things to Think About

Solar Panels on House Roof

A solar power system is a substantial investment with a long lifetime (over 25 years) so it’s a good idea to think about the condition of the roof on which those panels are mounted and how the immediate surroundings may change during that time.

The Future of Your Roof

If you are thinking of roof mounting the panels, make sure that your roof will last for this time period.  If your shingles need replacing now is the time to do it – before mounting the solar array. Shingles with a longer warranty (35 years or more) or other roofing materials such as metal would be a good choice. A lighter color of roofing material will last longer and also keep your house cooler in the summer.  Once the panels are up, they will have to be temporarily removed and then reinstalled for any roof repairs.

Landscaping and Building Plans

Solar panels work best if they are not shaded.  Do your landscaping plans include trees that will grow and eventually shade the solar array?  Are you (or your neighbor) planning a future garage of shed that will block the sun?  Look at those possibilities when you plan the location for your solar panels.

Call us toll-free at 1-877-441-2355 if you are interested in a site assessment to determine your potential for solar power.

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