Featured Solar road

solar everything. then we will start reversing global warming with a double effect.

 

We don't currently have the resources to put solar on everything. Cost effectiveness and budgeting are still essential.

I don't currently see how PV sufficiently ruggedized for road surface applications could possibly be as cost effective as PV rooftop installations and PV-integrated roofing materials. When I converted my house to a Net Zero home, all my PV went onto the roof.

 

i guess you have to think possibilities, not current technology. i like the roof shingle idea, i hope it is in the near future. snowfall is a problem, maybe can be solved with some sort of heating system.

 

we have a cape with a steep roof, but i have to rake the snow off, or we get ice dams. a metal roof might work better.

 

What is causing the ice dams? My understanding is that most of them are the result of poor insulation, allowing excessive interior heat loss to melt the roof snow from below. The melt water then refreezes somewhere else before it can leave the roof. To prevent this, (1) improve ceiling insulation below the roof, and (2) improve attic ventilation so that the remaining heat loss mostly convects out air vents, rather than melt snow.

An additional benefit of this is reduced heating bills.

But you will still need to mechanically remove heavy snow that risks exceeding roof load limits.

 

it sounds good in theory, but in an old cape, easier said than done. i also built a new colonial a few years ago. the insulation was all properly done to code, and correctly over the outside wall soffit area, with soffit vents, baffles and ridge vent. but we still had ice dams under certain conditions.

btw, the proof of your theory happened a few years ago when we got 14' of snow. the water was running down the inside of the dining room wall until we turned the heat down and left for florida.

 

Meh! Never tried turning back the tide then?

 

no, but i'd like to turn back the clock.

 

Nothing you can do but get the snow off so the melting from the bottom doesn't reference (refreeze - darn autocorrect). I heard metal roofs don't help either. Ice has formed in between the connectors and water still gets in. It's less of an occurrence but an occurrence no matter what

I was told by a contractor nothing helps except getting the snow off. Not even heat tape. If you're in a 70 degree house with a foot on your roof beware!

 

i'm trying the heat tape now.

 

Doesn't solar work best when angled towards the Sun, and not shaded by trees ?

This road and the bike path look like make work projects. just spending money, francs, euros.

 

Yes. But. That is not sufficient reason to throw away the vast resources of solar energy that fall on non-ideal surfaces. As solar collection hardware gets cheaper, it becomes economical to harvest many non-ideal locations too. My home has significant impairments from neighbor's trees, but I was still able to achieve Net Zero at a cost acceptable to me.

For now, I see roofs as much lower hanging fruit. But at some point in the future, those roads and paths and other surfaces will possibly become economically viable too. Targeting (or at least considering) all existing human-made impervious surfaces will help conserve the remaining biological surfaces and resources.

 

i think it's important to start these experiments now. in 20 years, we'll be glad we have the data.

as always, i'd love to see them paid for with a gas tax.

 

A cold, double roof might help. Not sure of the technical name, but it is simply a second roof installed over the first with a gap in between. Vented at the peak and soffits, cold air can circulate between the snow covered top roof and insulated bottom roof. This keeps the snow from melting from underneath.

 

Scott Brusaw's Solar Roadways in Sandpoint, Idaho is working on U.S. projects.

" Brusaw has been comparing the embedded solar cells flat on the ground to conventional rooftop panels angled toward the sun. What he found surprised him: "We were within 5 percent of theoretical values."
. . . . Would Solar Roadways Work? A Government Engineer Discusses the Controversial Technology | Greentech Media

Sounds like the Solyndra cylinder, "The solar panels developed by the company were claimed to be unlike any other product ever tried in the industry." (wikipedia.) . . .

 

We can do a thought experiment first.

Solar roof versus ccgt power plant - more expensive per kwh but costs are going down. Helps reduce risk of future rises in fuel prices and effects of ghg.

solar roof versus on shore wind - more expensive per kwh. Often coincides with peak power usage, scales down easier, more places can have solar roof than on shore wind.

Solar road versus solar roof - lower up front cost, lower maintenance costs, more appropriate areas, lower cost per kwh, lower risk, lower ghg per kwh.


So you see in the first 2 cases solar has some advantages over wind and natural gas, but likely will be a smaller percent. In the last you find that roof is much better than road, so if you are going to move funds to roads then its likely a bad decision from a public policy and utilatarian concept.