On January 15th, PURE and the DCMA, Dufferin County Museum and Archives hosted "Wind Power on Your Property", a 2-hour seminar featuring the very much in-demand Dr. Jim Salmon of Zephyr North, who has over 15 years of experience in providing wind resource assessment services to the energy industry.

Here's what I took away from the excellent talk by Dr. Jim Salmon of Zephyr North, at the PURE public meeting on January 15th. Basically, there's a lot of math involved, and numerous things to consider when trying to obtain power from the wind. Here's the main formula used to calculate wind "power density", a critical measurement when analysing your power potential:

Power Density = 1/2 × (air density) × (wind speed)³

What's important in this formula are the relative terms. Note that power increases linearly as air density rises, but increases geometrically (cubed) as wind speed rises. So double your windspeed, and your power factor increases by 8 times! A small, sustained windspeed advantage, gained for example by a higher tower or better location, could make all the difference for commercial success. As well, air density apparently can vary by as much as 40%, depending on temperature and pressure. Cold winter winds are much better than summer breezes.

Our formula can be expanded:

Power = 0.5 x (air density) x (wind speed)³ x (rotor area) x (various efficiency factors)

Those factors include things like generator and gear-box efficiencies, but note the other term. As rotor area increases, your power increases in linear fashion too (eg. double the rotor area, double the power). And don't forget that a wind turbine's rotor area is a function of the square of the blade radius, so double the radius, and you quadruple the area!

Anyway, enough math. The other factors that Dr. Salmon talked about included topography and surface roughness. Smooth, like the surface of a body of water for example, is way better than rough, like a village or forest. This factor can affect your power capture by quite a bit, and explains why the best sites for wind farms in Ontario are near or in the Great Lakes. Obstacles, such as barns and trees, can be critical for turbine placement, so stay away from these if possible.

Topography takes into account such things as hills and valleys, slopes and ridges. Locating on a ridge which is perpendicular to the prevailing wind is usually best. Ridges are better than hills, because the wind can't just flow around them. Moderate slopes facing the wind are good too.

PS. for further info, visit Dr. Salmon’s Zephyr North website, at: www.zephyrnorth.com

A "wind rose" diagram illustrates windspeed and direction over time.

Most of us know that wind in Dufferin County is a major untapped resource, likely to become increasingly valuable in the near future. We believe that wind electricity generation has the potential to produce large economic benefits. Dufferin County must decide how best to manage this resource for the benefit of its residents. In order to do this, County and municipal councils need accurate information about the extent and value of the wind resource in our region.

Therefore, a PURE committee has been struck to investigate the establishment of a wind monitoring program in Dufferin, and we invite those members interested in this initiative to get involved. The monitoring program will benefit many stakeholders in Dufferin County. These including Municipalities, farms, business and residents considering wind systems.

In our proposal, Stage 1 of the program will consist of wind monitoring equipment and data loggers, situated on an existing tower structure in the target area. This set-up will produce a continuous log of wind direction and strength for one year. Data will be collected at 3 levels, between 10 and 46 meters (30 to 150 feet).

Later, the equipment would be moved to other locations. It would make use of existing towers where feasible but eventually might require the purchase of a tower. Analysis of the data will provide information about wind energy (kilowatt hours) per year, wind velocity ranges (used for turbine selection), captured at 3 height levels.

In terms of needed equipment resources, these would include 3 wind metering devices, a data logger, radio modem with base station, one PC, an Internet account, a telephone connection and a web site. Required personnel will include 3 to 5 volunteers to mount the hardware on the tower then monitor the data and provide access to the data through the Internet.

Accurate wind data will aid PURE members in establishing small-scale wind installations. By working together we can develop a plan to gather this essential data, which will be useful for many projects to come. Wind is a community resource, and it's up to those of us who live here to make sure it is developed in a way that benefits all community members.

Join us on Earth Day, April 22nd, at CDDHS: Centre Dufferin District High School, to celebrate completion of the Green Power Project. Phase One of the PURE-initiated renewable energy demonstration project at CDDHS in Shelburne is now in place and we are on track to complete the full wind and solar powered system by Earth Day, 2005. Stay tuned to the PURE website for details!

Both the high school and the Upper Grand District School Board were excited last year when PURE proposed the idea of an on-site renewable energy system. In fact, our expectations have already been exceeded!

Students are learning to monitor what they now call the "Green Power Project" on an ongoing basis, conduct tours for other students and members of the community, collect data and gain valuable hands-on experience with a working renewable energy system. Teachers in the Science and Technology departments are working with PURE members to develop curriculum materials focusing on energy conservation and renewable energy technology, and make the best use of the system.

PURE Board members Matt Fairlie and Randy Dryburgh, along with Jeff Wellman, Assistant Head of Science at CDDHS, have coordinated the effort to get the system up and running. When completed, the system will consist of 0.5 kW in photovoltaic (PV) panels, 7kW of battery storage, a 1.5 kW wind turbine on a tilt tower, a grid connection using a "net meter", a power inverter and other monitoring equipment.

Many other generous supporters donated time and materials to make this project happen, and we thank them for it. In particular, electrician David Lutka was instrumental in getting us to this point. He gave up much of his after-hours time to help with various installation tasks. Not only that, but he took on a leadership role in the project, getting students involved, spending many hours to coordinate their efforts, and that deserves special mention.

The completion of Phase One of the project - 12 PV solar panels, battery storage and energy monitors, was celebrated at a public meeting at the school on Nov. 30, 2004. Students from the school Environmental Club chaired the event, which included tours by the Physics class students who helped install the PV array. Other partners who have supported the Green Power Project include the UGDSB, Hydro One, Canadian Hydro Developers, the Fairfield Group and Fines Hardware, all of which were on hand for the celebration, as was Brampton-area MPP Linda Jeffrey. The student hosts read letters of support from the Minister of Energy, the Minister of the Environment and the Canadian Ambassador for the Environment, and they distributed Green Tags to the partners who supported the project. Each Tag represents the one Kg of CO2 that will be avoided for each kWh the Green Power Project produces, once it is connected to the grid.

The PURE-CDDHS Coordinating Group are presently working with Hydro One on connecting the system to the Ontario power grid and the installation of a "smart meter" which will allow computerized monitoring of energy use in the school. Soon, the wind turbine will be mounted on the roof of CDDHS, with target date for full operation at the end of March.

After looking into various renewable energy projects I soon came to realize how much work was involved in trying to calculate and justify their expense. Collecting all the necessary information and tailoring it to my specific goals was difficult and time consuming. Fortunately, Natural Resources Canada has developed a free and extremely comprehensive software system to ease this task, called "RETScreen", a case-study-based tool that helps any project planner better analyze the technical and financial viability of potential renewable energy projects.

RETScreen helps to determine if Renewable Energy TechnologieS (RETS) are viable at the critically important planning stage.

Formally, "RETScreen International Clean Energy Project Analysis Software" is available via the internet and CD, and is a unique decision support tool developed with the contribution of numerous experts from government, industry, and academia. The software, provided free-of-charge, can be used world-wide to evaluate the energy production, life-cycle costs and greenhouse gas emission reductions for various types of RETS. The software also includes product, cost and weather databases; and a detailed online user manual.

RETScreen can significantly reduce pre-feasibility costs. Renewable energy topics include:

and RETScreen software also provides:

• Product data, with over 1000 suppliers represented
• Weather data from over 1000 ground stations
• Satellite-derived surface meteorology and solar data
• Background on the different technologies, with over 50 international case studies of real world projects
• Greenhouse gas emission info
• Financial analysis calculations

This new PURE committee hopes to host its first meeting sometime in March, for those interested in discussing wind power on their property or in their community. We’ll aim for an interactive forum were individuals will get the chance to exchange ideas and ideally form working groups to pursue particular projects. For more info please contact Chris Kotwas at 519-925-1710.