Focus on Sewers

Would've been nice to see a bit more showcase on sewer heat extraction in this article - it's a technology almost every municipality can make use of. Water in a sewer generally runs at about 15-20ºC, which is 4-5x higher temperature than groundwater that would be used in a ground-source heat pump system.

Current estimates of energy offsets from liquid-stream sewer heat extraction are in the range of 1 home heated for every 10 connected to the sewer. The drawback is that generally only new developments and institutional buildings are likely to benefit.

Then, once the sewage reaches the treatment plant, the sludge (biosolids) left over from the treatment process are anaerobically digested to produce methane gas and fertilizer (Nutrifor). This process is in place at several BC treatment plants including Annacis and JAMES (The author should do a bit more research before claiming there are no anaerobic digesters here).

BC's"clean?"hydropower

Colleen,

I was surprised to see someone writing for the Tyee start their article with "British Columbia's abundant hydropower means our hands stay almost clean of dirty electricity imports." This gives people the impression that the Liberal Governments policy of giving private corporations our creeks and rivers is a good thing!! This electricity is going to the US and is not for us. (see Vancouver Sun front page Saturday, June 21). We will still be importing "dirty" energy from Alberta because it will be cheaper. British Columbians need to know that we are in danger of losing BC Hydro. A Crown Corporation that works for us and puts profits of almost $1 billion a year back into our schools, hospitals and social services. These profits will now be leaving the province and the country. It is educational to go to www.ourrivers.ca and see some excellent videos on this topic. It is also valuable to go to the Independant Power Producers website, www.ippbc.com to see how they have lobbied and influenced our government for many years. Giving away our water for pennies, destroying the ecosystems of every creek in the province that can produce energy (900 of them), building miles of transmission lines,is not green! Sadly, our hands have never been dirtier.

Correction

You're right, UnCivilizedEngineer, this:

"there are only 15 digesters in all of Canada -- and none in British Columbia yet."

is incorrect.

I was referring to on-farm digesters, which should have been clear in the story. There is interest in this technology for farms specifically because of the amount of methane released from manure.

Although no agricultural waste digesters exist yet in B.C., Catalyst Power Inc. recently received $1.5 million from the Innovative Clean Energy Fund to build the first one, in Abbotsford.

cogeneration

Why is there no discussion of this.

Ideally buildings should only be heated by downstream waste heat from generating facilities. The generated power would be sold on the grid at a favorable rate or used locally.

All large office/apartment buildings should be forced to use this method of heating. Several small buildings could share a plant amongst themselves.

Only El Gordo's archaic provincial net metering policies stand in the way.

One stroke of the pen

One stroke of the pen from well written legislation would require "geothermal for all new public buildings and all P3 projects", and a second stroke of the pen, would provide the legislation authorizing the fiscal means to put retrofit geothermal in existing public buildings over a "X" year period of expenditure. Consider public schools, all heated by natural gas, a significant carbon emitter, yet all have sufficiently large playgrounds or fields to put in place a geothermal -loop heating system.

With respect to the City of the Vancouver, and their $50 billlion dollar property endowment fund which is primarily just collecting interest, neither used for affordable housing or meritorous projects, consider this: establish a City of Vancouver Geothermal Utility, select a demonstration neighbourhood, rip up the sidewalks on both sides of the streets, install geothermal loops down one side, then cross over, loop down the other side, feeding the homes along both sides of the streets. Result: homeowners get significantly lower heating & air conditioning costs, less natural gas gets utilized (less throughput of natural gas means more sustainability of that depleting resource), less carbon emissions, and the City of Vancouver Geothermal Utility gets guaranteed revenue flows to allocate to other worthwhile endeavors. Will this occur? - you decide whether either Vision, NPA of COPE has the moxie to think of this or actually do this. I have other ideas pertaining to transport, rather than electrifying cars ..we need to electrify the highway..and there is a way to do that too, rather than having hundreds of millions of batteries around from electric vehicles - which is not sustainable at all. bcpolitics.ca

one more comment

better yet, create "City of Vancouver Energy Utility" - and why not use part of that $50 billion Property Endowment Fund....I can see in my mind a multitude of renewable initiatives coming out of that..all to benefit the people of Vancouver and the environment. ..

Peter D and schools

I think you have a great idea about geothermal in schools. I would like to see a combination of ideas to go with the geothermal. Firstly, we must note that most rural schools use the school field for their rather extensive septic systems. Digging geothermal loops in beneath rural septic fields could be expensive and dirty, but not impossible. In retrofitting existing buildings, mechanical/furnace rooms are already hooked up to centralized heat distribution systems; the new equipment could be attached to the old system, holding costs down.

Using heat recovery of the effluent after the septic tank before it moves to field could provide some bonus heat, as the transfer of heat from a liquid is much quicker than from air or the soil. For city schools, theheat can be recovered before the sewage leaves the property. Schools, however, don't use much hot water so it is not like taking the heat out of Vancouver apartment building sewage.

One of the problems with schools is that that students are subjected to continual florescent lighting. Though florescent have improved, this light is not optimal for many students, particularly some of the most frail (think fetal alcohol and autism). Therefore, schools should be built to make more use of indirect, full-spectrum light from the sun. Passive solar energy collection should be incorporated in building design when possible. They should use wind turbines and PV cells on their roofs that are used to power the lights and the pumps for the geothermal. Any extra power generated during summer months would be sold to the grid.

Once this equipment is installed, understanding of how it functions should become part of the school's curriculum. The students should get used to understanding and assessing the energy being created for them. It should be more than text and lecture style teaching. Field trips schould be taken to the roof and to the furnace rooms when kids are young. High school students should learn to understand the schematics. In this way, we can have citizenry that understands much more about energy. They will understand that there is more to energy and water than flipping switches and turning taps.

BC companies could become adept at the retrofits and market technology, skills and designs around the world.

multiple technologies

The big problem here is artificially produced economic constraint. High tech solar cells are priced so high that only the rich could contemplate them. But there are many lower tech strategies, and possibilities for bringing costs down through economies of scale and redesign of the way we do things.

For example building on a glass patio cover situated to the sun allows you to concentrate heat and store it in a suitable heat sink. A well insulated pit full of stone would hold the gathered summer heat for use during the first few months of winter, maybe beyond Christmas if it's a lot of stone. All you'd need are the glass room, the stone pit, some ducting and a couple of small fans. A perfect compliment to a heat pump if you want, though that would cost more.

Add on a couple of efficient little wind turbines ($600 each at Canadian Tire)and batteries to run the fans, a black painted water preheater could be placed inside the solar porch.

Retrofits are more expensive always, but designing this into a new house would cost very little more than current standard building. Heat sinks are efficient storage for heat, and rocks are almost free.

If somebody designed a small scale methane recovery unit for household waste, that would be another thing. Methane will make a flame, and propane fridges and freezers can be easily adapted to burn it. Very low tech and accessible idea. The methane will be released anyway, we might use it to reduce our dependence on other sources. It would be better than a regular composting toilet, which are available off the shelf.

Lots of ideas, lots of possibilities, mix and match them to compliment each other and enhance our lives, and forget the fifty year debt.

fireworks?

Unfortunately many people see the old fireplace as their money-saving device.
They already have the pick-up and chainsaw, wood is plentyful in many areas (including salt-soaked driftwood).
We have a culture that worships open flames and nobody cares about pollution as long as they save money.
Perhaps our government should spend advertising money on no-smoking referring to fireplaces?
Perhaps new construction should have mandatory energy saving fireplaces if at all?
Of course, there is no point in mentioning that fireworks also pollutes,is there?