Science·What on Earth?
- Ropeways replace polluting trucks while generating clean power
- Floating solar panels are making a splash
- Increase in illegal clam digging in B.C. could raise risk of deadly poisonings
Ski lifts that carry cargo? Ropeways replace polluting trucks while generating clean power
Trucks that spew carbon dioxide and toxic pollutants are often crucial for transporting cargo. But in some cases, there’s a cleaner alternative — ropeways similar to the lifts that skiers use to get to the top of a mountain.
Bonus: They can generate green energy.
That’s something Toronto-based Torex Gold does at its El Limón-Guajes mine in Mexico. Every hour, its “ropecon” — a ropeway/conveyer belt hybrid — moves 1,000 tonnes of crushed ore to a processing facility 1.3 kilometres away. (Check out the video here.) Bernie Loyer, vice-president of projects for Torex, said the company studied options for transporting the ore 380 metres down the very steep mountain, and concluded a ropecon would be cheaper and safer than trucks.
The system, installed in 2016, generates a megawatt of electricity through regenerative braking (the way electric vehicles and flywheels do). That’s comparable to the power generated by a wind turbine.
“It’s not a lot of power, but it’s rare that you get an opportunity to move a thousand tonnes an hour at no net energy cost,” said Loyer.
The technology isn’t new. Ropeways or aerial tramways have been used for centuries to transport materials and cargo, and were still in use in Canadian mines in the early 1900s. Since then, they’ve been largely supplanted by trucks, which could transport the huge quantities required by modern mega-mines.
But there’s renewed interest. Doppelmayr/Garaventa Group, an Austrian ropeway company that makes gondola lifts and cable cars, designed a new material ropeway system in 2001 after a customer requested it, said Silviu Varzecu, sales engineer for the subsidiary Doppelmayr Canada. Since then, it’s been installing about one system every year or two, mainly for mining companies, including Torex.
Varzecu said such systems can cross obstacles such as rivers and cause little disturbance to the environment. Some are as quiet as a dishwasher, he said.
While there aren’t any material ropeways operating in Canada right now, a B.C. mine aims to be the first.
Thomas Gardiner, director of environmental, social and governance for Taranis Resources, got in touch with us following our article on gravity energy storage, and says valuable ores on mountaintops are kind of like a natural, pre-existing gravity battery.
Gardiner has been working with Varzecu to design a ropeway for a mine near Revelstoke that the company is starting up again at a deposit that contains silver, gold, zinc and copper. In the 12 years he’s worked on the project, Gardiner has driven up and down the “bumpy, jagged, nasty mountain road” to the mine many times. “We started to consider, well, what’s it going to take to upgrade this road?”
Millions of dollars, he estimates, along with impacts such as logging. And the end result would be lots of noisy, polluting trucks going up and down a steep, hazardous mountain road.
Instead, in about five years, for a slightly higher initial cost, he hopes to build an aerial tramway that could move 14 tonnes of ore per hour 3.8 kilometres — 812 metres of it downhill — while generating 300 kilowatts of clean power. The electricity could potentially be used to charge electric trucks to carry the ore to be processed.
Gardiner added that once the mine is depleted and cleaned up, the ropeway could transition to a new role. “It’s already a pretty popular area for skiing. You know, you can just turn the thing into a chairlift.”
In response to Jennifer Van Evra’s piece last week on Canada’s position on climate change refugees, Philip Lucas wrote:
“I agree we need to seriously consider how to help climate refugees, and should not leave action on this ‘file’ until a disaster is occurring and people are dying or starving. Perhaps we should consider climate as a primary reason to accept refugees even over war and civil unrest. The latter are capable of being dealt with by the people themselves and with assistance from other nations diplomatically.
“Climate, on the other hand, is a monumental force that cannot be stopped. Yes we can resist the effects for a short time, but over time even the most robust interventions will not stand against Mother Nature. Though as we work on plans to accept those most in harm’s way as climate refugees we have to also take action to save people in Canada from these same climate threats. Trying to simply build barriers or rebuild after a disaster is short-sighted. There are thousands of people living in high-risk areas in Canada and we need to speak plainly and act with courage in addressing the reasons why these people must move.”
John Hd wrote, “Help these refugees live in their own countries by forcing their home countries’ political powers to take care of their own people. Stop refugee lawyers from exporting refugees’ problems to other countries.”
John Hamilton: “This is a very thorny issue. We certainly share the responsibility for the impacts of climate change based on our very poor record in combating climate change and our excessive lifestyles based on fossil fuel consumption, etc. However, we have already seen how ill-prepared we are to commit to the long-term support required to allow refugees to fully integrate and adjust to life in our country. A few months in a hotel room and a government handout to give refugees a start to a new life is clearly not sufficient.
“I believe we have to make sure we have all the necessary resources and desire to allow refugees whatever time they require to become established and fully independent contributors in our society. Otherwise, we will end up with large groups of people living in squalor and disillusionment based on unfulfilled dreams to create a life for themselves in Canada.”
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The Big Picture: Floating solar panels
As we discussed last week, solar panels have become a remarkably versatile and reliable energy source for families in war-ravaged Syria. Countries looking to make a larger, more concerted effort to harness the sun’s rays and cut carbon emissions need considerable space to build arrays with thousands of panels, which can be a challenge for smaller places. One option getting more attention is floating panels, which sit on the surface of bodies of water. Once you get past the idea of water and electricity in such close proximity, the concept has a number of benefits. In addition to being untapped real estate for smaller countries — such as Japan — these installations, by blocking sunlight, can reduce evaporation and algae blooms. Cool water can also make the solar cells more efficient for longer. There’s even research that suggests by shielding the water, floating panels could offset the effects of climate change in certain water bodies. The power potential is significant — for example, placing floating panels on just one per cent of the reservoirs in Africa could double the continent’s annual hydropower capacity. To date, India, South Korea and China (see photo below) boast the biggest, most impressive floating installations.
Hot and bothered: Provocative ideas from around the web
- On Thursday, the Canadian government announced a program to provide homeowners with a rebate of up to $5,000 for energy-saving measures, from erecting solar panels to installing more efficient windows and doors.
- The sighting of a giant river otter in Argentina last week was a cause for celebration for environmentalists, as it means that the animal, which hadn’t been seen since the 1980s, is not in fact extinct. In the words of the conservationist who spotted the creature in the Bermejo River in northeastern Chaco province, the sighting produced “an incredible feeling of so much happiness.”
- Oil companies are increasingly feeling the heat over their climate plans. The latest example is a decision by a Dutch court forcing Shell to cut its emissions by 45 per cent (from 2019 levels) by 2030 in order to meet the goals of the Paris Agreement.
Increase in illegal clam digging in B.C. could raise risk of deadly poisonings
Flora Qu admits it is hard on her back, but says digging for clams seemed like a good way to get out of the house given the pandemic restrictions.
“First time [I’ve] come here,” she said Monday, as she and a friend spent a couple of hours digging at Centennial Beach in Delta, B.C., just south of Vancouver. “Just want to exercise and have fun.”
Qu said she was unaware that harvesting shellfish like clams and mussels — called bivalve shellfish — is illegal in B.C.’s Lower Mainland, but believed her friend had purchased a licence online.
Full closures have been in effect for around 50 years for bivalve shellfish harvesting across the bays and inlets of Metro Vancouver and up the Fraser River because of pollution and naturally occurring toxins. Bivalve shellfish are filter feeders, which means contaminants in the water can build up inside them, experts say.
And it could be deadly to humans who eat them, say fisheries officials, who are worried that people aren’t paying heed to the warning signs posted at beaches across the region.
Qu said she’s not worried about getting sick. “Make the soup. Cook a super long time and it’s clean,” she said.
Officers with Fisheries and Oceans Canada (DFO) say they’ve been running into people with a similar attitude at an alarming rate since the pandemic started.
“It’s about three times the number of encounters,” said Art Demsky, a DFO detachment commander.
If consumed, naturally occurring toxins produced by phytoplankton in the water can lead to diarrhetic, amnesic and paralytic forms of shellfish poisoning. Paralytic shellfish poisoning is potentially fatal.
Demsky said stopping illegal harvesting is a priority, but their efforts are limited by the number of officers they have and the vast area they cover.
Crabbing is legal when in season and done with a licence. There are limits and size requirements on what is caught.
Richard Wong regularly comes to Centennial Beach to go crabbing, and has seen a large uptick in people digging for clams.
“I try to tell them… you shouldn’t be picking up those things,” Wong said. “But then when we walk away and turn around, they start picking again.”
Tira Chow started crabbing last year and has been surprised by how many people she sees gathering buckets of clams.
“I mentioned it to a couple of people, but they just ignore you. So I just think there should be more signs posted,” she said.
Chow and Wong both feel the English-only signs posted are not enough, and need to be in multiple languages. Demsky said that’s difficult given the variety of ethnic backgrounds of the people they are encountering. He said DFO has pamphlets in various languages and has put information out on social media and in newspapers in different languages.
The BC Centre for Disease Control (BCCDC), which tracks cases of illnesses, is trying to make it easier for people to know the rules. It is launching an updated website this week showing all the locations of closures, and a guide telling people exactly what the different shellfish look like.
“A lot of times the poisonings we get, people said, ‘Oh, I harvested some clams.’ And when we ask them, ‘What type of clams did you harvest?,’ they don’t know,” said Lorraine McIntyre, a BCCDC food safety specialist.
She said three people reported becoming ill from shellfish in April, but noted many people don’t report illnesses and some cases can only be confirmed by testing the contaminated shellfish and not the person. As for the idea that you can cook your way to a safe clam, that is simply not the case, McIntyre said.
“While cooking will prevent you from getting bacterial illnesses, it’s not going to do anything with the toxins,” she said. “They are resistant to cooking. And, in fact, sometimes the toxins get more potent after cooking.”
McIntyre said it is crucial for anyone who feels unwell after eating shellfish to contact their doctor or poison control immediately.
And while illness should be a deterrent, Demsky said so, too, should fines. People caught illegally harvesting shellfish risk tickets starting at $250, with additional fines for each shellfish up to $100,000.—
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