TCL&P looks at biomass plant, more windmills to heat portion of city

TRAVERSE CITY – If you've been cringing as you fill your gas tank lately, wait until you get your next natural gas bill. Going into the heating season, gas prices are projected to be some 30 percent higher this winter than last. The time is now to invest in other sources of energy and the Traverse City community is doing just that.

If a proposed plan proves feasible, a community renewable energy project could break ground within a couple of years in Traverse City.

Traverse City Light & Power (TCL&P) was recently awarded $400,000 to study the cost-effectiveness and capabilities of an energy plan that would utilize a biomass plant and additional windmills to meet the heating and electricity demands of a large section of the city's west side.

If the dollars make sense and the community is behind it, then wood and wind will heat and power a district spanning approximately 1.5 square miles, including a residential population between 6,000 and 7,000, as well as Munson and Meijer.

Local energy economist Steve Smiley, who has served as a consultant to Light & Power for many years and is heavily involved in this project, is thinking big with this study.

"I'm coming from a focus of 100 percent renewable energy for the community," says Smiley. But it can't come from only one source. He adds, "To get 100 percent, you have to integrate renewable energy."

This means wind, this means sun (read about NMC's new solar lab pg. 20), this means biomass, organic material from plants and animals. So, the primary question of the study is this: How can a local community implement renewable energy in a cost-effective and integrated manner to meet 100 percent of the electric and heating needs?

It is the hope that biomass (in this case wood chips) and wind will prove to be the answers. If so, what will begin with just the city's southwest corner will eventually spread out to cover the city limits.

A community solution

TCL&P has been looking at renewable energy sources for a while, conducting analyses over the last two years for a biomass-based heating system in the Grand Traverse Commons area. Additionally, biomass, solar, and wind energy options have been studied as part of a "Rebuild Michigan" grant with the Traverse City Area Public Schools (TCAPS) and the Bay Area Transportation Authority (BATA).

It is the hope that the current study will be the final step toward a renewable energy plan and that construction of facilities can begin by 2007. In addition to TCAPS and BATA, other active partners in the study include The Village at Grand Traverse Commons, the State of Michigan building, and Northwestern Michigan College.

"This is a community-based system," says Smiley. "We can do this in our community, by the community, because we have a community-owned utility." That is not the case, he adds, with utilities in most large cities.

In June, The Michigan Public Service Commission awarded a total of $6 million in grants to 11 organizations to promote energy efficiency. The Light & Power award was the only one for a district heating and wind power plan and the only one given to a utility, says Jim Cooper, key accounts and marketing manager for TCL&P.

The municipal utility has had initial conversations with the businesses, schools, and healthcare facilities located in the study area to gauge interest, says Cooper, and has received 100 percent positive feedback. "They are very interested in cutting heating costs in half," he adds.

According to Smiley, natural gas currently costs over $10 for a million British Thermal Units (BTUs) of energy, but was $5 only three years ago. The present market for biomass is just $2 for a million BTUs, so the savings that can be realized by burning biomass for heat are very real.

TCAPS is a major player in this study because its schools are large community facilities that consume considerable power. Of the nine Traverse City public school buildings on the TCL&P electric system, three are located within the study area. Recent studies have shown that TCAPS can produce cost-effective renewable energy for those nine facilities.

How biomass works

How the biomass plant will ultimately be designed and where it will be located are key components of the work that lies ahead for the Light & Power team and its partners in this feasibility study. The basics of how biomass systems work utilizing wood chips involves something called a gasifier. Basically, wood chips are heated (vaporized), and gases are released. Those gases (hydrocarbons) are volatile and when air is induced, they combust. The resulting flame enters a boiler (a big fire box with water tubes) and travels throughout it, producing either hot water or steam that then gets piped to heating loads.

"It's one of the cleanest ways to burn wood," says Smiley, adding that very little ash is left behind and a very small amount of particulate matter is expelled from the system. This type of gasifier burns at 80 percent efficiency compared to a typical woodstove that burns at about 50 percent. A critical part of the system, Smiley points out, is sustainable harvesting of the biomass.

While a variety of scenarios will be tested to produce the most cost-effective and viable construction, one possible facility design proposes wood chips arriving by barge to the former coal dock just north of town and stored in a main biomass plant nearby. Then, several smaller systems could be strategically placed around the city. The smaller systems would be used to boost the heat when it has to travel longer distances.

Powered by wind

A solitary windmill sits in the middle of a field atop M-72 west of the city, producing some 800,000 kilowatt hours of electricity per year. When it was erected in 1996, it was the largest one in the country at 160 feet tall. Now, it's on the small side.

To supplement energy generated by biomass, TCL&P will also examine the feasibility of building additional, larger windmills. This portion of the study is an expansion of the TCL&P Green Rate Wind Project, in which some 125 customers agree to pay a higher electric rate in support of wind energy, as well as new BATA and TCAPS wind initiatives.

The plan calls for locating good wind sites (most likely west of town) and include a short-term wind power output forecasting system. The wind towers would be the latest generation of tall tower (260 to 390 feet), large capacity wind turbines in the 2 to 5 megawatt peak output size range.

Cooper explains that wind is more consistent at higher altitudes, and in our moderate wind area with limited available land, the tall tower turbines are necessary to meet the kilowatt goals for wind-generated electricity in the study district.

A waiting list of people wanting to get on the "green rate" speaks volumes about the social support for wind energy. Results from TCL&P's "2005 Customer Research" survey, presented by Northwestern Michigan College's Research Services in June, showed clear support for windmill construction and continued financial support of the "green rate."

"TCL&P is unique," Cooper says. "We have a really environmentally-conscious population." Cooper is cognizant, however, of some residents' aversion to the structures, especially since new windmills would be taller. He says the utility recognizes that any social concerns would need to be remedied for the project to be successful.

Can a local community implement renewable energy to meet 100 percent of its electric and heating needs? Now that the study is underway, we're about to find out.