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Reusing waste power improves efficiency

I have written about out need to "change our relationship with energy." What do I mean by that? For the most part, we treat energy as disposable. We use it once and throw it away without thinking of the consequence.
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I have written about out need to "change our relationship with energy."

What do I mean by that?

For the most part, we treat energy as disposable. We use it once and throw it away without thinking of the consequence. We could be doing more with our energy which would decrease our impact on the environment at very low cost or even with a net benefit.

For example, the local pulp mills put out an awful lot of heat. The clouds coming out of their stacks isn't pollution, but hot water vapour emitted to form clouds. Heat is generated to run the processes and then discarded.

I am not saying the pulp mills are doing anything wrong. They re-use heat as much as possible but they still have plenty of extra which could be used in other ways.

In Europe and Japan, the location of some mills is specifically chosen to allow waste heat to be used for buildings and even roads.

The heat warms water which is circulated and used in radiators. This makes sense and is better all around.

Doing this in Prince George would be difficult because of the location of the pulp mills and the town. However, the heat could be channeled into a heating system to support greenhouses along the north bank of the Neckako.

Such a system would likely be able to sustain dozens of hectares of greenhouse operations, which could then be used to grow local produce.

Just think - potatoes, lettuce, squash, or whatever, grown on the north bank and shipped to local markets. This would be a good use of the waste heat from the pulp mills, getting it to do double duty.

It would also mean the produce grown would not need to be shipped very far cutting down on the emissions involved in transportation.

Not practical or possible, you say? A Quesnel company is already doing this as they have greenhouses under cultivation for growing seedlings using the waste heat from one of the mills in Quesnel. If it can be done in Quesnel, why not here?

Another example which would reduce our energy footprint is the use of winter cold to cool the summer. We live in a town which is frozen for a good portion of the year. We heat our houses all winter to keep us warm. But come summer, when it warms up, we turn on the air conditioner to cool our houses down. Wouldn't it be better to store some of the winter cold and use it in the summer? It makes sense but you can't go outside and get a jar of cold to store.

However, there is a very effective way to keep the cold around. Water freezes. Frozen water can be used to store the cold winter temperatures and then used to run air conditioners and cooling systems in the summer.

What's involved? Not a lot really although it is generally only employed for large buildings such as the university, the hospital or CN Centre. Still, it is little more than pouring water into a pit and letting it freeze. Then adding more.

Every now and then, a layer of sand or hay can be added for insulation to help slow the melting in the spring. And ideally, you would want to have a lined pit to minimize cold water losses to the ground.

However, the amount of ice generated during our winter could go a long way towards cooling our buildings in the summer thereby minimizing energy demands. Again, this is an idea being employed in Scandinavia. It was once used in North America.

In the southern portion of Washington State, there are lava tubes in the ground where local merchants would store ice in the winter and harvest it in the summer. Locally, northern residents used to carve ice from lakes and store it in buildings. Refrigeration put this practice to rest but it is still economically sound.

We could also be a little smarter by utilizing natural waste to generate electricity. Specifically, manure from cows. Studies have shown a herd of 1,100 cattle generates enough manure to run an anaerobic digester, which can generate 5,500 kwh/day.

Not a huge amount of electricity but consider that the waste would naturally generate methane if left on its own and methane is a much more powerful greenhouse gas than carbon dioxide. Instead of wasting the energy in the methane, we should capture it and generate electricity. Surely this is a better thing to do with cow manure than just releasing the gases to the atmosphere?

It is time to think smarter about how we use energy if we are going to tackle the problem we face. We need to think differently about our relationship with energy and where it comes from.