The earth rotates 360 degrees in 24 hours which is 15° per hour or 1/4° per minute.
The apparent elevation angle of the sun in the sky changes ±23 ½° (from solstice) over the course of a year at a maximum rate of .016° per hour (.384°/day).
This Apricus evacuated tube solar hot water collector is located at 53.5 degrees north latitude, near Prince George, BC. The 30-tube collector is mounted on an Apricus stainless steel frame which is tilted to optimize production during winter months. This angle also reduces the output somewhat during the summer to reduce over heating. The house is not situated at the ideal angle so the collector faces east of true south.
The steep angle helps the snow to either slide off the collector or to not stick in the first place. During the winter of 2008-2009, the first winter of operation, the area received a total of about 1.2m (4 feet) of snow but only two days of hot water production were lost due to snow on the collector.
The winter performance of this collector has far exceeded the owner's expectations. In February, there were over 3 weeks of clear cold days with overnight temperatures dipping to -35°C and daytime highs of around -20°C (zero on the antique scale) With two people in the house, the 300 liters (80 US gallons) of hot water storage was almost sufficient to carry over the few cloudy days.Another unexpected benefit of this high mounting angle is that in the summer, late in the day when the sun is behind the collector, it shines on the back of the tubes and the collector keeps producing hot water.
2011Performance
Data
2010 Performance Data
2009 Performance Data
Apricus.com
(manufacturer's
web site)
Solar Space Heating
Information
This array supplies the power for an off-grid residence that is located a few kilometers north of Prince George.
The autumn colours shown here are typical of this area. Although some people complain about our winters, it is truly a great place to live!
Surrette 927amp-hour batteries used in a 24-volt system near Prince George. These double-walled batteries are suitable for use inside a home. Each of these 6-volt batteries weighs 310 pounds.
(model 6CS25PS)
A
backup power system using solar and wind. Too bad the photographer didn't hold the camera level. I'll try to do better next time.
An older system using a pair of Trace modified square wave inverters for 120/240 vac power.
This
system has been upgraded by replacing the original solar charge
controller with an Outback maximum power point tracking (MPPT) unit.
The array was then re-configured to operate at twice the battery
voltage, reducing power loss in the cables to 1/4 its previous value.
A 1970s vintage Dunlite wind turbine rated at 2kw continuous, 3kw for 4-hours. This unit was re-built and installed near Prince George.
For more information about Dunlite wind turbines and the early history of the Dunlite company, follow the link at the bottom of this page.
This
flat plate solar domestic hot water (SDHW) system is located in the
College Heights subdivision in Prince George. The collector is mounted
on the garage roof , facing south-south-west. The low angle relative to
the sun optimizes hot water production in the summer when the sun is
the strongest. The collector feeds a drain-back system to preheat the water that is fed to the existing natural gas water heater.
The Dunlite wind turbine blades are close to 4 meters (13 feet) in diameter. The pitch of the blades changes to prevent over-speed operation in extreme winds.
This Enerworks flat plate collector installation in the Hart Highlands subdivision of Prince George was a challenge because of the 12/12 pitch (45° angle). We had to work off ropes and scaffolds and over the skylights.
Performance Data
The Enerworks package added to a standard electric hot water tank makes a nice neat installation.
When you shower, you are both using and dumping hot water simultaneously. The heat that is being wasted by dumping it down the drain can be recovered with a drain water heat exchanger.
At the left is a photo of a Drain Water Heat Exchanger like the one I installed in our home. I was unable to get a good photo of ours so I asked WaterCycles for these pictures. The photo on the right shows a shorter unit for locations with insufficient room for the full length model.
A drain water heat exchanger is installed vertically in the main drain line leaving the house. The sewage goes down the inside copper pipe and the water feeding your hot water tank flows through the copper tubing that is wrapped around the large pipe.
This unit recovers the waste heat from the drain water and uses it to preheat the cold water that is feeding into your hot water tank. Based on personal experience, I can confirm that the temperatures shown in the animated illustration on the manufacturer's web site are accurate. (I used a Fluke 80T-150U temperature probe and a Fluke digital multimeter)
There are several sizes available and they are made in Canada by WaterCycles.
This small 12-volt DC only solar power system is used to run the equipment in a store at an off-grid tourist attraction. The blue box is a cellular telephone range extender that picks up the signal from staff and guests cell phones and re-transmits it using a high gain directional antenna that is mounted on one of the buildings.