Snow–free roads seem like a beneficial thing for most modes of transport though.
This is the most inefficient way to remove snow. There are other options.
Is it though? I’d be curious to hear a more efficient method… Certainly, mobilizing a fleet of snow plows and salt trucks isn’t more efficient in any sense of the word.
Yeah, it actually is more efficient to plow. It’s grossly inefficient to melt ice into water.
See this xckd what if: https://www.youtube.com/watch?v=WYf9-xfm6t8
It starts by using a flamethrower (because the series is supposed to be about silly questions taken seriously), but it eventually converts everything in terms of joules. That can be easily converted into the necessary electrical output. Which is a lot of electrical output. Just a sick amount of energy.
Plowing is easily better. But yes, salt is an issue all its own.
I think the xkcd was Moreso a Proof that melting large existing quantities of snow is incredibly difficult. If They’re proactive with it and start running it before the snow pours then I’d assume its a lot easier to melt comparatively smaller quantities of snow over a large hot surface area.
I do agree that this requires people be smart and proactive and we haven’t seen a lot of that lately. But hey, this is something they’re being proactive about. Though it seems a little strange to assume they won’t at least test and use the new expensive infrastructure they put in, no?
The power use is exactly the same. You are melting the same quantity of snow, but over a longer period of time.
In fact, it might be worse to pre-warm, because a lot of power will be wasted into the air.
Dog, you can’t be lecturing people about their lack of understanding thermodynamics, and then mix up power and energy.
This is a pretty simplified and reductive take. How much electricity does it take to power a snowplow that can weigh as much as 30 tons with salt for all surface street miles? Is the freeze-thaw-freeze cycle plus weight damage to the road more efficient by cost/resource use? What about snowbanks as a hazard and visibility obstruction?
And that’s putting aside all the ecological damage salt causes or that these systems can often recycle waste heat. Your video about a car traveling highway speeds melting multiple inches of snow isn’t a gotcha for a completely different situation.
A Manhattan city block, on the short end of the rectangle, is 264 feet. A typical road lane is 12 ft across. Assume two road lanes and 4 inches of snow, getting 2100 cu ft of snow.
Using this snow weight calculator, fresh snow of that size will be 6,589.4 - 9,229.4 lbs. Let’s take the midpoint of 8100 lbs. That’s 3 million grams. And from here on, I can do the rest in metric.
Assuming it’s at 0C already, it takes 334 Joules to melt 1 gram of snow. It will take 1.2GJ to melt the amount above.
There are electric snowplows being tested in Norway with 1000 kwh battery packs. That’s 3.6 MJ. Quoting the article: "In light to moderate snowfall and temperatures as low as minus five degrees, the truck covered a total distance of 293 kilometers (km) at an average speed of 47 kilometers per hour (km/h). "
Yes, snow plows are more efficient. It’s not even close. You can chop off orders of magnitude and it’s still not even close.
I really, really need people in this thread to understand thermodynamics. Melting ice takes a fuckton of energy.
Maybe these can be useful to hybridize the system, where you plow normally and then melt the little remaining to avoid the use of salt. As a total replacement, no. That’s a laughably bad idea.
You’re really caught up on energy efficiency, civil engineering is not just thermodynamics. Energy is becoming incredibly cheap, before the current administration derailed our energy sector, we were on track to hit $0.03/kWh for utility scale renewable power by 2030. For reference, that’s about $10 to clear that city block.
And again, systems like this and the more famous one in Holland MI are generally run on waste heat (from a power plant, wastewater treatment plant or datacenter), so that math doesn’t even apply. Looking only at energy cost leaves you tripping over dollars to save pennies.
The real costs are and always have been infrastructure. Yes, it’s not possible to use this as a drop-in everywhere. It highly depends on the usage/wear of the road, space constraints, upfront cost of installation, maintenance, access to a heating solution, etc, etc… Even with this hydronic layout the main costs are the transmission lines, the cost to heat them is minor.
It’s very weird to see so much resistance to this in an anti-car community, as if pedestrian and micromobility infrastructure doesn’t need snow removal too.
Energy is becoming incredibly cheap
Not an excuse for wastefulness. The numbers here are so great that a good sized city would need a nuclear reactor brought online just for this.
systems like this and the more famous one in Holland MI are generally run on waste heat
That’s fine if it’s available. It’s usually heavy industry that’s providing that. If you don’t have a convenient heavy industry to provide that, then move on.
It’s very weird to see so much resistance to this in an anti-car community, as if pedestrian and micromobility infrastructure doesn’t need snow removal too.
What of it? There’s perfectly good plows for walking and biking paths, too.
Melting ice takes a fuckton of energy.
The counter here is that oftentimes, snow melting systems like in the OP use waste heat that would otherwise get sent into the atmosphere or a lake. There is no power being generated specifically for melting snow. Using waste energy could be seen as a “free” way to melt the snow.
