Wind Power
Wind power is the top-of-mind alternative energy source on the Prairies, especially in southwestern Alberta where stong winds are common. It is generated from turbine systems that convert the kinetic energy of the wind into mechanical energy or electricity.
The amount of power harnessed from the wind hinges on the average annual wind speed, which is influenced by topography and obstacles, says Katrina Lakenman, an AgTech Centre Research Assistant. "It is recommended that at least one year of wind data be collected before selecting a site."
A proven technology. Modern aerodynamics and engineering have improved wind turbines to the point where they can provide reliable, cost-effective, pollution-free energy for individuals and communities. The cost of these systems depends directly on the power output. A 1-kW system costs about $5,000, and a large-scale commercial system that produces 600 kW can cost $1 million.
Consistency is key. Wind systems need a relatively consistent wind flow. A wind power system usually requires an average annual wind speed of at least 15 km/h. An average wind speed of greater than 25 km/h is desirable, over 29 km/h is excellent, especially if the intent is to sell the power. Trees and other obstructions can impede valuable wind flow to the rotors. Rotors should be placed to take advantage of the stronger winds at higher elevations. Towers are typically placed 100 metres from the nearest obstacles. The middle of the rotor is placed 10 metres above any obstacle that is within 100 metres.
Renewable and clean. The forces of nature continuously generate wind energy. "Wind power does not use fuel, produce greenhouse gases or by-products," says Lakenman.
Solar energy
The sun provides an unlimited supply of energy in the form of electromagnetic radiation. Capturing enough solar energy for effective use depends on available solar energy, weather conditions, location, the technology used and the application.
"Solar energy is almost unlimited and is a renewable energy system that can stand alone without connection to a power or natural gas grid," says Sherry Perih, with the AAFRD Engineering Branch.
Economic benefits. "Operating a solar energy system for buildings is much lower in cost than operating a combustion furnace with an air conditioning unit," says Perih. "However, the cost to install a complete solar system can be higher than the cost to install a furnace and air conditioning unit."
On farms, solar energy can be used in a number of ways.
Solar heating of buildings. Buildings designed to harness solar energy for heating typically have large, south-facing windows. Materials that absorb and store the sun’s heat can be built into the sunlit floors and walls which collect heat during the day and slowly release it during the night when it’s needed most.
Other solar heating design features include sunspaces and trombe walls. Sunspaces, similar in construction to greenhouses, are built on the south side of a building. Sunlight warms the sunspace and a ventilation system circulates the heat throughout the building.
A trombe wall is a thick, south-facing wall painted black and made of a material that absorbs heat. A pane of glass or plastic glazing, installed a few inches in front of the wall, helps hold the heat. The wall absorbs heat during the day and slowly releases it in the building during the night.
"Design features are also available for retaining cool air in the summer," says Perih. "For instance, overhangs can be built to shade windows when the sun is high in the summer and sunspaces can be closed off from the rest of the building. Buildings can also be constructed to use fresh air ventilation in the summer."
Solar water heating. These systems capitalize on the sun’s energy to heat water for building heating. Most solar water heating systems for buildings have two main components, a solar collector and storage tank.
Photovoltaic systems. Photovoltaic (PV) cells convert sunlight into electricity. PV cells are often used to power calculators and watches.
"PV cells are usually designed into modules that hold about 40 cells. About 10 of those modules are mounted in PV arrays that can measure up to several metres on a side," says Perih. About 10 to 20 PV arrays can provide enough energy for a household. For industrial applications, hundreds of arrays can be interconnected to form a single PV system.
"The initial cost of solar energy technology is the biggest impediment for producers and others thinking of adopting the technology. For example, a 50 watt panel can cost as much as $600." she says. "But the costs also depend on the application. It has the potential to reduce energy bills considerably when used exclusively or as a complement to other energy sources."
Biodiesel
Producers using diesel-powered tractors need to look no further than the nearest canola field to find a source of cleaner-burning, high-performing fuel. Biodiesel, an exciting new fuel option, is derived from plant or animal oil.
Easy to adapt. "Biodiesel is similar to petroleum diesel," says Kelly Lund, of the AAFRD Engineering Branch. "Using biodiesel does not require changes to existing engines, fuel infrastructure and storage."
Blending with petroleum diesel is also an option, she says. Lubrication is improved even with biodiesel blends as low as one percent, she says. Biodiesel-fuelled engines deliver similar mileage, torque and horsepower. "Winter operating procedures are the same for biodiesel as they are for number two petroleum diesel."
Environmental benefit. Carbon dioxide emissions, total particulate matter and carbon monoxide emissions are reduced with biodiesel. Nitrogen oxide emission, however, seems to increase. But that is mitigated by the fact that biodiesel does not contain sulfur, making catalytic converters more efficient at reducing nitrogen oxide releases. This would not apply to most agricultural diesel engines, which don’t use catalytic converters, but even so, there would still be an overall net benefit as far as emissions.
Cost effectiveness. The cost of biodiesel depends on the plant or vegetable oil source. "Producers may be able to obtain sufficient quantities of waste vegetable oil to meet fuel requirements with minimal or no charge," says Lund.
Biodiesel costs
 | Biodiesel
Waste Oil | Biodiesel
Farm Oil | Market
Purchased Oil |
150 L Batch
(Cost of finished
biodiesel per Litre) | $.48 | $.83 | $3.03 |
450 L Batch
(Cost of finished
biodiesel per Litre) | $.47 | $.82 | $3.02 |
Since biodiesel is currently not available for retail sale, producers must find their own source or produce it themselves, she says. A simple, biodiesel batch reactor that can produce 150 litres of product at a time would cost less than $400 to construct. A 450-litre batch reactor would cost just over $1,100 to build. "However, if a farmer produced three 150-litre batches per week, it would take three and half weeks just to make enough biodiesel to supply a typical day’s fuel requirements," she says. "Production can increase with scale, but producers would have to factor in additional storage space for equipment and fuel."
The capital cost of pressing canola seed to obtain its oil on farm is prohibitive, especially for experimenters, she says. An appropriately sized press costs $18,000 to $20,000. "Farm production of biodiesel is viable, but the current economics of farm production don’t encourage it."
Commercial biodiesel is widely available in Europe and may be available in Canada later in this decade. |