Home Heating with Evacuated Tubes

This article describes a home built by someone in Big Bar Lake in BC. Approx. 200 kms NW from Kamloops. The homeowner planned right from the start to try and heat the house with solar water Heating.  
When trying to incorporate any renewable energy project into a building, it makes more sense to make sure the home is as well insulated and efficient as possible in the first place as this will minimize the non-renewable energy you need to replace. This article describes the system and the house to help other people who are wanting to install solar water heating in the home. Remember that this system will also apply to commercial buildings as well.

Sizing Solar Hot Water Tanks

A solar tank is a critical part of your solar hot water system. The type and size of solar tank you need is often a poorly understood part of a system, mainly because there are so many variables to it.
Many systems installed by companies often attached a small box of tricks to the side of your existing domestic hot water tank. The justification for this is partly that often you don't have room for a bigger tank in many mechanical rooms and it also saves you buying another larger tank. While this is true, it also means that your solar system will store very little heat during the good sunny days.
This article will also describe various types and sizes of solar tanks that can be used for solar water heating. It will describe pressurised and un-pressurised solar tanks including some places you buy them from. It is also part of a longer article on heating homes with solar hot water using a real life example of a home using a large 1700 gallon tank.

Solar Collector Efficiency Explained

All solar collectors, evacuated tubes, flat plate collectors and un-glazed pool heaters have different efficiencies. This is why no one can say Evacuated tubes are always better than flat plate collectors. It depends on their application.

Calculating collector efficiency is complicated and not easy to do without a computer and not all collectors reports will show a graph like the one below.

Solar SRCC and CSA Rating

Are you looking at buying "CSA approved solar collectors". This article explains what is now in place in Canada regarding Solar Water Heating.

The end of the EcoENERGY program.

The residential and commercial Eco ENERGY incentive programs are ending soon, 31st March is the deadline, after that, as far as we know there are no more Federal Solar Water heating incentive programs going to be announced anytime soon. There are a few provinces that have some local or provincial incentives still running but these are few and far between.

For the past few years, a list of the collectors that were acceptable to receive the incentive was maintained by NRCan. The NRCan list said that all collectors on this list "met CSA Standard F378-87 or equivalent". Latitude51 Solar were one of about 90 companies with a few collector models each who were on this approved list.

Note this line: it is important and has significant relevance later when the CSA basically admitted that NON of the Collectors on this list can be classed as "CSA approved"


Grants for Solar Hot Water

In this email we will cover these topics.

  1. If you are looking to install a solar water heating system you are most likely wanting to know how the grants work and what you need to get them.
  2. Explaining what the new F379 is and what it does for you.  This will give you some valuable information about what to install and what not to install on your solar water heating system.

The old incentive scheme ended for solar water heating ended March 31st, 2011.  It was replaced shortly afterwards with a new scheme, but it had some radical changes to the program.


Peak Oil

There are many reasons why people install solar energy systems, either solar hot water or solar PV systems.

  1. Protect themselves from rising energy costs.
  2. To reduce their Carbon footprints.
  3. To go off grid
  4. Peak oil

Until you understand peak oil all discussion of what future energy prices are is a pointless exercise. Hopefully this article will give you a better understanding of why solar is THE most important technology for everyone.

Solar Tank Size

One 30 tube panel should be sufficient for a house with 3 people (approx. 10 tubes per person, should provide 30% to 60% of the total yearly hot water. This will be approx.. 100% in the summer and 30% or less in the winter.
The 30 tube panel is suggested with cylinders up to 260 liters / 60 - 80 Gallons
If your cylinder is larger then it can be heated with more than one panel. It is possible to add an extra panel to an 80 gallon tank if you aim to benefit from higher temperatures in the wintertime but it must be designed for coping with any overheating that is likely to occur in the summer.

This is a very simple answer to a big, complicated question!  

For a longer and more detailed discussion detailing sizing your solar tank visit here - Pressurised and un pressurised solar tanks.

High Temperature Insulation

When you insulate the pipe work to and from the collector. Make sure you use insulation that will resist the high temperatures. The pipe work can reach very high temperatures and normal insulation is likely to melt. The flexible stainless-steel pipe comes pre insulated with high temperature insulation.

Solar Maintenance

Very little maintenance is required for solar water heating systems. You should occasionally check the system pressure, to make sure there has been no water loss, and to check for any air in the system. The only other requirement is to ensure that there is always an electricity supply connected at all times, otherwise without pump circulation, in strong sunshine, the panel could overheat. Over heating is OK for a while but it can cause the glycol in the system to break down prematurely. The over heating can be a serious issue if you have not used flexible steel solar piping or copper pipe for the plumbing.

Is my roof strong enough

The solar panel weights about 80kg - this is really not much weight for a roof. There should be no reason to strengthen a house roof prior to mounting the solar panel. However if you are fitting a panel to an old roof, you should check the timbers are not rotten or sagging. If in doubt ask a roofing contractor to check.

Roof Mounting Angle

 Some very common questions about mounting collectors on your roof include...

  • What angle?
  • Which Direction?
  • Solar PV or Solar Water Heating?
  • I don't have a south facing wall?
  • Can I mount them on a wall?

Snow on your solar collectors

 "I've read somewhere that evacuated tubes collectors get covered in snow but Flat plate collectors don't".....

.. don't believe the hype... both types of collectors, evacuated tube and flat plates will at some point collect snow in winter. If you have a few days of snow that will make both Evacuated Tubes and Flat Plates be covered in snow, then they won't produce much heat until the snow goes.

Look at the picture below

How to calculate solar energy

This article will show you how to calculate the energy produced by solar collectors and how this relates to the size of tank you need.  It will also show you what to look for in selecting a solar collector for your project and the cost per BTU.

Our collectors are like a Kettle!, once you know the power output of your collectors you can easily work out how much hot water they are likely to produce and work out how big a tank you will need for the solar system.

Why solar works

History of solar collectors and how they work

Obviously solar energy comes from the sun, but how do we capture it.

Back in about 1767 a scientist Horace de Saussure created the worlds first Solar Oven. This consisted of 3 layers of glass surrounding a well insulated box. Sunlight passed through the glass heating up the box and the layers of glass trapped the heat in. This was in effect probably the first Solar Collector.

True cost of oil & gas

This payback depends very much on the price of natural gas. Right now the "price of gas" is very very low. $5.84 per GJ on a latest gas bill. Sounds cheap? Try and work out the payback on a renewable energy system using this cost for gas. Its a very hard?   The quoted "price" has increased on average about 10% per year for the last 10 years and reached about $13 per GJ not too long ago.

Solar Water Heating

What is solar water heating and how does it work?

This is a question that gets asked a lot. This article will hopefully give you some basic information about solar water heating systems and what they can, and cannot do for you.

In a nutshell we use a very simple technology to heat the water in your home or business using the sun. Solar water heating has been around for a very long time and does work very well in Canadian climates. However, how effective it is depends on where you live in Canada, this article will give you a good head start on finding out what can be done to heat buildings with solar.

Heating a garage

In Canada because of the huge demands for winter heating, solar heating can be very costly. that's not to say it can't be done, just don't expect it to cost less than a $1000 gas furnace or normal natural gas hot water boiler!

It really all depends where you live.  Obviously heating a garage in Vancouver is much easier than in Alberta.

Why buy Latitude51 Solar

Why would you buy Latitude51 Solar collectors? It a simple question, we will highlight a few points we think you should consider.

Solar Collector Size and Power Output

They are large (over 4.6m2) powerful collectors, although they are priced very low and they are imported, they are not "cheap imports". We looked long and hard for a collector which had a good track record from the OEM and had a good result (ie high power output) from the test report. See the actual heat of the collectors in Calgary on the live data link.

Solar Flat Plate Versus Evacuated Tubes

When you read the endless sites that profess how much better one type of collectors is better than another you need to learn how to compare the performance of various solar collectors for yourself.

This applies not just to the Flat plate vs evacuated tube debate, but also to any other solar collectors.

No one collector performs the same in every climate. It all depends on where you live and what the climate is where you live.  This article will help you make that decision for yourself.

Commercial Solar Grants

There is a misunderstanding that only collectors that have SRCC test data or CSA appred collectors were acceptable for the EcoENERGY commercial solar hot water heating grants. This was not the case. Under the EcoENERGY grant program for commercial solar water heating systems the government maintainer a list of acceptable solar collectors.

Latitude51 Solar Collectors were tested by the TUV facility in Germany and were accepted by EcoENERGY on their List of accepted collectors.

How strong are evacuated tube collectors?

The tubes are made from high strength Borosilicate Glass, they are very strong. The Vacuum is what makes them very efficient, insulating the heat inside from the "cold climates" outside. If the vacuum does fail, then the performance of the tube effectively drops to that of a Flat Plate Collector!

There are 30 tubes in each of our collectors. The most likely time the tube will be damaged is during installation, once its in place, then its very unlikely to break. The tubes are warranted by the factory for 10 years from manufacturing defects.

How to install a solar hot water system

These three videos will show you a lot of information about building and installing a system for yourself. 

The videos show installing the tubes, building the frames and custom racking and takes you though how a system can be set up for heating a 200 gallon tank.

  1. The evacuated tubes are easy to install and this video shows you how to do it for yourself.
  2. The operation of the Solarbloc Solar Pump Station.  Navigating the menu on the Solarbloc.

Evacuated Tubes - How hot can they get?

Part of the process of installing the system is to make sure there is no airlock in the pipes between the pump and the solar collector. If you get an airlock or a blockage it means the fluid cannot flow round the system correctly and the fluid (water and glycol) will sit in the collectors heating up until it boils. Once the airlock is removed the system works perfectly.  This video is just to show you can boil water with an evacuated tube solar collector.

Solar Thermal in the News

Contact us for a Free Commercial Solar Simulation Design Services 1 800 759 8990

Watch Solar Water Heating Video

Watch this great video on solar water heating systems.


Live Monitoring

See a solar hot water system in Calgary and Vancouver here.

Photo Gallery

Image of some Residential and Commercial Solar Water Heating projects.

Online Store

Buy solar systems for DIY install, prices and technical details can be found here.

Solar Heating Design Layouts

See some of our most popular Pre-Engineer Solar Water Heating Packages available for domestic hot water, space heating and pools.

Solar Water Heating Articles

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SolarWater Heating Projects

About Us

Latitude51 Solar Heating System are distributed across Canada ,USA, Mexico and Caribbean. We are a North American Distributor for solar water heating equipment. By eliminating the traditional wholesale distributors, we sell direct to contractors and home owners across North America so they can buy our solar at affordable prices. We are forever expanding our network of distribution locations around Canada and USA. If you would like to join our team then call us at 1 (800) 317-9054

Installer Locations

  •  Vancouver
  •  Winnipeg
  •  Saskatchewan
  •  Edmonton
  •  Calgary
  •  Okanagan
  •  Los Angels
  •  New York
  •  Minnesota
  •  Chicago
  •  Seattle


Contact Details

Address: 835 Kapelus Dr. West St Paul, MB R4A 5A4, Canada
Phone 1 800 317 9054
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