Frequently Asked Questions
Here is a brief list of some of the more popular questions relating to alternative power solutions. If you have a question that is not answered here, please email us - Thank you.
Solar energy - Is it for me?
If you have a need for electrical power and conventional hydro is not accessible,
or undesirable, you have an application for solar power! Some of the more common uses are power for a remote cottage, a boat without access to shore power, or a
mobile home. Even people who have hydro access but don't want the hassle and expense of burying cable, can take advantage of the benefits of Solar Power. Photovoltaics is a wonderful energy source, the fuel is free, safe, silent, and reliable and of course, environmentally friendly! It does however, have its limitations, for example, running high demand loads like air conditioners. Please Contact Us for additional advice and information.
Electric baseboard heating, hot water heating and stoves are examples of energy
gluttons! The first step in implementing any Alternative Power solution is to
examine your current energy loads and work to become a more sensible power user.
Conservation is key! You can still enjoy all the modern conveniences of a
grid-powered home, but you'll tread lighter on the environment while enjoying
the benefits of producing your own power!
What is electricity?
Electricity is energy we have harnessed in the past 100 years. By definition, electricity is the energy available from the movement of electrons within a conducting material such as a copper wire. To help you visualize electricity we often use the analogy of water flowing through a hose; the electrons are like the drops of water. Enough electrons (water drops) with force behind them can be used to do useful work. Volts, Amps and Watts. The common units used to measure the quantity of electricity are:
- Volts: Electrical force or pressure behind the electrons in a circuit. Analogous to water pressure or PSI, it tells us the system voltage (12, 24).
- Amps: The number of electrons flowing past in a second. Like gallons per second in a pipe, it defines the electrical current in a wire.
- Watts: Total amount of electrical energy, per second.
Power Consumption: Amp Hours and Watt Hours
In power systems we describe the total amount of energy consumed over a certain period in either amp hours or watt hours. A one amp draw for four hours has used a total of 4 amp hours (AHr) of current. A 100 watt light bulb over 24 hours uses 2400 watt hours (WHr) or 2.4 kilowatt hours (kWHr) of energy. Note: a kilowatt equals 1000 watts, and a kilowatt hour equals 1000 watt hours. Your local hydro unit charges per kilowatt hour used. Types of Electricity: AC Versus DC Current. Just to make things interesting, electrical energy is moved from place to place in two ways. Alternating current (AC) is the most common form; utility power arrives to us as high voltage AC current. Alternating current is like water sloshing back and forth in a bath, the same electrons doing the work in one spot. Solar panels and batteries produce direct current (DC), which is easier to store. DC current is usually used at lower voltages, i.e. 12 or 24VDC.
Advantages of Higher Voltages
In all power systems we have to move electricity from one place to another. The transfer is not 100% efficient, and we have to take care to minimize the power losses en route. In wire, the loss of electrical power is a factor of the resistance of the wire, and the amount of current going through it. If we use higher voltages, our current is less, so power losses will be lower.
Wind Power - Is it for me?
Good sites for wind power will have average wind speeds of 16 to 24kph or more. There are locations on the coasts, prairies and in the arctic where wind systems are ideal as a primary power source due to the consistency of the wind speeds. Most places in Canada may have strong winds occasionally, but lighter winds most of the time. In this case, wind power is an excellent supplement to other charging sources. Wind power can compliment solar power, and in many places, this will give you this most power in the winter when sunlight is at a premium.
Wind Generator Ratings
Manufacturers pick a nominal wind speed at which to rate their wind generator, but there is not a standard wind speed that is used. Different models will perform better in lower wind speeds and others are designed for high wind areas. Comparing wind generator output curves will tell you the expected performance at each wind speed. The current output from a wind generator increases as the 'square' of the wind speed, so don't expect a lot of power at low wind speeds even though the unit seems to be turning quite quickly.
Wind Site Selection
Steady winds without turbulence are a must for maximum power. The higher the wind generator is placed, the stronger the winds it will experience. Avoid trees and buildings that will shadow the wind generator. Placing it close to the batteries will minimize the line loss and cable size. Propellers and wind generator vibration can cause a certain amount of noise. Placing the wind generator away from living quarters is recommended.
Wind Generator Installation
Access to the wind generator may be necessary, so a guyed tower with rungs is ideal. Spending time on top of a tower is not always fun, so making the wind generator easy to remove is a good idea. An electrical junction box is better than spliced connections as it makes disconnection easier. Hardware should be corrosion resistant and greased, especially in coastal areas. Due to the height of towers and distance to the batteries, long cable lengths with wind systems are common. There are advantages to using higher voltage systems. Consult a wiring table and keep the line losses below 5% over the cable run.
Wind Generator Maintenance
All wind generators have moving parts. Bearings, brushes and shafts will all need occasional maintenance. Equipment exposed to salt water may need more frequent servicing than inland sites. Wear and tear due to normal operation can be fixed with replacement parts; however, this is not covered by the warranty. Wind generators may be subjected to severe storm winds that can cause damage. Two blade models are more vulnerable than smaller fan blades due to extra vibration. Plastic blades are more durable than wooden blades. In very high winds, the wind generator should be switched off with a stop switch.
(Water Power) Micro-hydro generation - Is it for me?
If your property has an adequate source of flowing water, then a small hydro system may be the most economical way of generating electricity for your home. Small hydro systems are simple, reliable and usually produce more power when you need it most, in the winter. To take advantage of hydro power, your water source must provide both volume and pressure (head). If your creek or stream can deliver more than 45 litres (10 gallons) per minute, then you will have enough volume. Pressure is derived from the height the water falls vertically, called head, and expressed in meters or feet. A small hydro system needs at least 10 feet of head to provide usable amounts of power. A small hydro system needs a turbine, alternator, and water jets aimed at the turbine, and a control circuit. You will also need a battery storage bank, regulator, and enough plumbing to get the water to the turbine, usually a 2" pipe or larger.
Why do I need an inverter?
If you have a DC power source and you require AC power (either 120V or 220V), you'll need a power inverter. A power inverter converts your 12 or 24V DC system to AC so that you can run your AC appliances. Please Note: Some AC equipment is sensitive to the 'quality' of the inverted power, so we recommend you contact us before selecting your inverter.
Two basic types of inverter output:
- Modified Square/Modified Sine Wave: Creates alternating current (AC) in 4 steps per cycle. Will run 90% of appliances, exceptions include some laser printers and cordless battery chargers (which brands have problems is a matter of trial and error). Some equipment will hum or experience interference from this inverter power.
- Sine Wave: Creates AC in upwards of 50 steps to closely approximate utility power. Will run any load with little or no hum or interference. Cost of these units is much greater.
Inverters are sized according to the loads that are likely to run at any given time +20%. An inverter's input voltage is matched to the battery bank used in the system. Inverters greater than approximately 800 watts in size do not have fusing on their DC input side and require an appropriate inline DC rated fuse - contact us for more information. The output of an inverter is connected to the AC breaker panel (main or sub panel) as if it were normal utility. All household wiring beyond the breaker panel can then be done according to standard building codes for AC, with some extensions - contact us for more details. The installation of an inverter should follow the manufacturer's recommendations in their installation guides. Some special features offered by inverter manufacturers:
Built-in battery chargers (stand-by models)
Allows a generator or utility line (i.e. RV park service) to be connected directly to the inverter as back-up or intermittent system support. The inverter will provide AC from the batteries. When the generator or utility is present the inverter transfers this power to the household appliances (loads) and uses what excess there is to charge the battery bank with its built-in charger. When generator is shut-off or utility is disconnected, the inverter will switch back to inverting from the batteries without disrupting the power going to the appliances. This is usually very quick at approximately 30ms.
Stacking interfaces
Allows two inverters to be connected together to provide 120/240 service. Remote/Automatic generator start: Trace Sine Wave series only, or via separate generator start relay.
How can I become more energy efficient?
More than likely, the simplest change you can make today is to use fluorescent lighting whenever possible! (they use 20% to 25% of the power needed by a standard light bulb) i.e. a 20W compact fluorescent bulb is equivalent to an 80-100W standard light bulb. Halogen lights are only about twice as efficient as standard incandescents, but many people prefer their light to fluorescents. Just remember, a fluorescent light produces the same amount of light as a bulb 5 times more powerful!
Check out our Products page for our indoor and outdoor lighting options!
Batteries - Which ones are right for me?
Batteries are the one component of an alternative energy system which require diligent maintenance. Each cell in a standard battery supplies 2 volts, so a 6 volt battery has 3 cells, a 12 volt has 6 cells and so forth. The battery's capacity is rated in Amp-Hours (or amps at the 20 hour discharge rate in some literature) We recommend the use of 6 volt deep-cycle batteries i.e.. GOLF CART) for most small to medium sized residential/cottage/cabin applications for the following reasons: Each cell in a 6 volt battery is larger than each cell in a 12 volt battery - thereby providing more capacity, better cycling performance (charging/discharging) and longer life. They are relatively inexpensive and easy to find are more easily replaced if a bad cell develops Flooded batteries Typical wet batteries with caps on each cell for topping up with distilled water. The least expensive form of battery. Sealed batteries Slightly different internal construction and acid requiring a lower charging voltage Will not gas as much as flooded batteries Marketed as maintenance-free as they do not require watering or new acid Much more expensive than flooded batteries NiCd (Nickel Cadmium) Good for small systems (i.e. emergency lighting) Very expensive compared to other batteries
Maintenance
All batteries should be tested every 3 - 6 months to ensure proper charging and operation. This is done by testing with an accurate volt meter while no loads are attached (open circuit), or with a hydrometer which measures the specific gravity of the acid (a more exact method for flooded batteries only). A full battery will measure 12.60 volts at rest A battery at 20% will have a voltage of 12.00 volts at rest. Do not add new batteries to an existing set which is more than 1 year old as the older cells will bring the new cells down to their current performance level. An older set which has been well used should ideally be replaced when increasing the size of the system. Do not discharge a battery below 50% of its rated capacity in order to ensure long life. The less a battery is worked, the longer it will last. Equalize battery bank every 1- 6 months depending on use to preserve performance - contact us for details.
If you have a question that you don't see answered here, please email us
and we'll get to it as soon as we can. The renewable energy industry is
expanding rapidly and there has never been a better time to consider Alternative
Power!
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