Work is wrapping up on a new ammonia refrigeration plant in the Community Centre, but it has hit a couple of delays, pushing it over budget.
A few weeks ago, the pipes were discovered to be too rotten to re-use, forcing an additional $60,000 in labour and material, though staff was able to do much of the work in removing the old pipes themselves, saving $90,000.
More troubling to council, though, was a recent report that says the new heat recovery system in the boiler mechanical room, concerns were raised about the space being too small.
According to a report to council, the smaller space could lead to contamination from the refrigerants, which could lead to premature boiler failure. “The combustion air for the boilers is drawn in from the outside, but, is not 100 percent sealed,” says a report that came before council at the last meeting. “Therefore, the possibility that contaminated air will make its way into the boilers is inevitable. And lastly, the heat in the room is questionable, and adding additional heat is a concern for the lifespan of all equipment and additional fan systems would need to be considered and installed.
The fact that it needs to be done is fine, says Councillor Chris Norbury, but he wonders why the decision is being made so late in the day, and if the District can spilt the cost of the last minute change with the company that proposed the original install in the first place. “Sometimes in cases like this, we have a contractor who came up with the plan, we can potentially split the cost. Is there an opportunity to do this in this case?” Norbury asked at a recent Council meeting.
While much of council expressed similar disappointment that this wasn’t considered when the quote was made, the additional costs were approved.
The ammonia refrigeration plant is used to maintain the ice. Currently, the heat is extracted and expelled outside into the outdoors using an evaporative condenser. “Following completion of the Heat Recover project, partially funded by the CleanBC Community Economic Recovery Infrastructure program, waste heat from the ammonia refrigeration plant will be used to meet the heating demands of the facility.”
This means that, rather than venting the hot air from the unit outside, they will install a new energy recovery condenser in the plant, along with a new high-temperature heat pump in the facility’s boiler mechanical, connected by glycol piping. “The energy recovery condenser will transfer waste heat from the ammonia system into a glycol circuit. The heated glycol will then be pumped to the heat pump in the boiler room which will then boost the grade of this heat to levels that are suitable to meet the heating demands of the facility, as well as distribute this heat to various facilities amenities.”
This will reduce the facility’s natural gas consumption by nearly 4,400 GJ each year, and operation savings over $70,000 annually. According to Polar Engineering, these carbon reductions are equivalent to planting 9,320 trees, taking 45 cars off the road, or heating 40 houses each year.
The heat pump will connect with the facilities existing two boiler loop systems—one to the arena and one to the pool. Currently, the heat for the facility’s is produced by three natural gas boilers. These boilers consume large amounts of natural gas and produce hundreds of tonnes of greenhouse gasses each year. “By providing heat to this boiler loop with the electrically powered heat pump, the natural gas consumption and greenhouse gas emissions of the facility’s boilers will be significantly reduced.”
But wait, as they say, there’s more. The heat pump will also provide pre-heat the hot water used in the facility. Currently, the domestic water is heated using a heat exchanger that is connected to one of the facility’s boiler loops. “By preheating the domestic water before it enters this heat exchanger, the heating load on the boiler loop will be significantly reduced. This will also reduce the natural gas consumption of the boilers by an anticipated amount of 65 percent.”
Proposed solutions included relocating the heat pump system to the ice plant machine room, but, this would require significant revisions, to the tune of $180,000+. Another proposal would be to move the system to the adjacent closet space beside the boiler room. Revisions required to do this include extending carbon steel water lines, electrical wiring, pipe, fittings, and hangers. This would cost $59,465.
That would put the over-run for the project at about $120,000, making the total cost to the district about $155,000.
While the final cost of the install will be around $1.55 million, most of that is being covered by grants, including funding from the CleanBC Custom Program. That grant included a study by Polar Engineering, who predict that the switchover will reduce greenhouse gas emissions by 61 percent, or about 205 tonnes per year.
The Lion’s share of the funding comes from a CERIP grant, which allows for capital upgrades to reduce carbon emissions. An additional $262,000 is being used from the PRA funds.
In the end, upgrades will include replacing the existing brine chiller, condenser, brine pumps, electrical system, and controls. The shell and tube chiller and evaporative condenser are being replaced with a low-charge plate and frame heat exchangers, leading to ammonia charge reductions of over 80 percent, which will also help reduce the Community Centre’s water consumption by an estimated 1.6 million litres per year.
According to Polar Engineering, this is a win-win-win. “This project proves that recreation facilities across BC can utilize grant funding to not only reduce carbon footprint, but also replace aging infrastructure, increase safety, and dramatically reduce operating costs.”
Trent is the publisher of Tumbler RidgeLines.
