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Comment by TedShiller | Hacker News Reader

Sounds cool until you read the article and realize it’s just wood with epoxy in it, so basically plastic

Yes, the material described there is not wood but an epoxy-based composite reinforced with wood fibers instead of glass fibers, like in PCBs, or carbon fibers, like in high-strength composites.

The only remarkable thing is that they have succeeded to match so well the refractive index of the epoxy resin to that of cellulose and bleached lignin, so that the composite is a clear transparent material instead of being just diffuse translucent, like most composites.

This might make this composite a better choice than polycarbonate or acrylic glass in many applications.

They should have given a comparison between the properties of the new transparent material and those of polycarbonate, because that is their main target market, not glass. Anorganic glass cannot be replaced by polymers in many applications, due to requirements for chemical resistance or high temperature resistance.

"This might make this composite a better choice than polycarbonate or acrylic glass in many applications"

It'd be great if it was cheaper. Even before the demand from the pandemic those were expensive.

Sand mining is causing environmental degradation around the world, to river beds, agricultural lands, etc. Taking that out of the equation could be a net benefit. Especially if it's at least as permanent as glass.

At least glass is basically perfectly recyclable though.

I think both creating and recycling glass requires intense heat, and so a large energy input. This process seems to very low energy requirements.

Perhaps not when you account the whole manufacturing process from fossil fuel to refined petroleum to raw epoxy to commercial formulas.

So an ideal candidate process for concentrated solar, then.

Sure but you could also just make a window out of plastic.

How much does it cost to get sand out of a safe area? I bet it's cheaper than making this.

Grinding up rocks to make sand works quite well. There are many videos of sand-making plants on Youtube and Vimeo.

The trick to this is designing crushers which work mostly by grinding rocks against rocks, not rocks against metal. Wear is much reduced.

Sand isn’t a uniform thing, for glass you can use wind blown sand from deserts because it’s melted. Which in practical terms is an unlimited resource as Si makes up 28% of the earths crust which is only behind Oxygen.

But, for extending beaches and most other uses you want textured sand that clumps together. As such people don’t mine river beds for large scale glassmaking as that sand is more valuable.

If it only diverts mining from near-lifeless deserts, that might be more acceptable. All deserts do have life though.

But what's the impact of cutting down trees + mining for some fraction of petroleum vs mining for glass? I would guess that it requires a rigorous and impartial analysis of the environmental impact.

There is very little danger of any world's deserts becoming sandless (or even making a dent in the amount of sand) due to the needs of glass manufacture.

I'm not even sure I'd call it a "danger." The Sahara creeping south is a danger. If we could make a dent in the amount of sand, it'd be a pretty amazing thing.

I was hinting that deserts aren't devoid of life, so it's still destroying some environment and habitat, even if it's one that humans have little value for. But, OTOH, felling trees is likely much worse.

Take sand out, put a bunch of highly processed synthetic polymers in. Sounds good for the environment.

If it proves to be more durable than glass, requires less energy, and also offsets demand for mining, it could be a net gain. I don't have understanding of the supply chain, and the environmental impacts of glass manufacturing to know.

Recycling could be difficult (once again, I don't have the domain knowledge), but that's only an issue if it needs replacing.

The energy to melt and process glass is for sure the big limiter here.

Then again, most polymerised epoxy is basically not recyclable -- once it has set, it's set. The most you could do to this would be to burn it.

windows glass isn't easily recyclable either. it can be repurposed...

> However, while window glass may not be recycled easily, there are many options for keeping it out of the landfill. For example, it can be melted and re-manufactured into fiberglass, incorporated into asphalt, and even combined into reflective yellow and white road paints. Broken glass can be combined with concrete to create terrazzo flooring and countertops. Some companies even use old glass for landscaping materials and other decorative applications.

...but that's nowhere near a recycled window.

Of you could toss the carbon you don't want into old coal mines (or just land fill) - why would you burn it and cause more global warming, we should be tossing our used paper into landfill, recycling it reduces the demand for growing more trees (and fixing more CO2

Right, let's conserve sand by extracting oil.

You gotta set priorities.

Think of it as a productive carbon sink for all that ancient dead organic matter.

Sounds like a horrible product once reaches the environment. At least glass isn't much of an issue and wood would just decompose.

Glass doesn't decompose, it gets eventually pulverized back into sand (naturally or manually).

The issue with glass though isn't how it's handled once we're done with it. The issue with glass is energy loss. We lose a huge amount of energy to the windows in our home, and it might be worth it to make wooden window panels if it means that we end up consuming less energy HVACing our homes. Especially since house windows can be expected to last for decades, which amortizes their disposal cost nicely.

No need to ditch glass for that reason. Use triple pane windows, they also block noise and have perfect seals.

In fact, triple pane windows are mandatory for all new construction in the EU as of this year[1]. I think double pane windows have been mandatory for years. Modern triple pane windows have less heat loss than the walls of most buildings built a couple of decades ago.

[1] https://www.buildup.eu/en/practices/publications/directive-2...

The R value of wood is not great [1] and would depend on the type of wood used and thickness. Double pane windows tend to have an R value of 1-2, which increases if filled with a gas [2]. Your hypothesis that we'd curb more energy loss is a bit misplaced without more nuance.

[1] https://www.energy.gov/energysaver/types-homes/energy-effici.... [2] http://www.engext.ksu.edu/buildingenvelope/windowsanddoors

Double glazed windows might be more efficient, but that's irrelevant if you simply don't use double-glazed windows. I know single-glazed is quite common in Australia, apparently because there's no local factory for mass producing double-glazed and there's no market base right now because it's so expensive because it's imported, so nobody wants to take the risk.

Probably less risky to open up a double-glazed window factory than it is to open up a transparent wood window factory.

Double glazed has been standard for at least 20 years if not 30 here in the Netherlands. It is primarily intended to keep warmth inside during colder periods. Newer projects tend to have triple or quadruple glazed glass with all kind of coatings. To keep the heat out in summer an infrared blocking coating is applied. In office buildings here it is more efficiënt to heat a bit more in winter due to loss of IR than to cool extra in summer.

Here in the Netherlands most everything newly built is built with double glass.

That is surprising given the amount of AC you use. I lived for a few years in a similar climate to Melbourne and double glazing made a huge difference in the Summer.

"so nobody wants to take the risk"

And everyone just uses more AC. Which surely is not more expensive.

Oh and right, thats the reason Australia absolutely needs coal to burn.

I’m not sure that’s true. We had gas filled double glazed windows made for us in Eltham, an outer suburb of Melbourne, during a renovation about 6 years ago. We replaced all the single paned glass with double panes. And we were on the edge of the Yarra valley, not particularly close to the city. So my experience doesn’t match this at all.

It's because it isn't true. There's a number of outfits and pretty much every new apartment building has double glazing. I've lived in 4 properties since moving to this country, 2 with and 2 without. Of those with, 1 new and 1 probably last renovated 15 years ago.

Drawing the blinds at night and for unused rooms will greatly reduce the heat transfer.

This article suggests that it's better to make windows of than glass.

So why are windows not made of plastic as we speak, very often?

Scratch prone?

A plastic window would need to be quite thick to be as rigid as a glass window. A plastic window would also scratch more readily, and it would likely degrade in the sun (become translucent rather than transparent). It’s not obvious to me that this wooden material somehow wouldn’t have the same problems.

Because the UV wavelengths in sunlight discolor and degrade most plastics over time.

Which raises the question of whether the same thing happens with this product, and if not, why not.

And as the article mentions, they used a marine epoxy. I haven't met a marine epoxy (or poly resin) yet that doesn't have to be coated to avoid UV damage.

They make window films that block UV and other wavelengths. I wonder if those can be applied to this.

They are - plexiglass. It’s just more expensive so only worth it for the shatter resistance at i.e. banks or stores in bad neighborhoods.

Lexan (polycarbonate) is actually used for that purpose. Plexiglas (acrylic) is also transparent, but not as resistant to impacts.

Plastic is more expensive, easily scratchable, and isn't as rigid as glass. Glass makes a lot more sense unless there is a very high risk of it shattering.

Plastic is more expensive?

The last time (before the pandemic even) I looked at glass and acrylic/polycarbonate sheets for a project, the glass was cheaper for a similar size. Maybe there are other plastics out there that are cheaper, but I'm not sure that they are suited for similar use. If they are suited to this type of use and are cheaper, then someone can make a good fortune if with the right marketing.

Oh, so not the material nominal pound for pound cost?

What do you mean? From a consumer perspective dealing with sheets, one requires dimensions for a project, not weight. Whether measured by weight or by dimensions, the glass was cheaper.

Also plastics scratch more easily. Something like plexy glass also breaks pretty easily similar to normal glass. Poly carbonate is much stronger but also quite expensive even when compared to normal glass. It also scratches easily.

Also because plastic gets scratched easily by dust blown in the wind, after about 10-15 years you can’t see through it.

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