The statistic of low Firefox use is based on accessing US government websites. Could it be that there is significantly LESS government site access by the population of users that prefer Firefox? As a corollary I recently read that game companies observed significantly HIGHER bug reporting from Linux users on Steam, not because there were more Linux-related bugs, but simply because that set of users were more likely to initiate bug reports. Of course Firefox is not Linux and Steam is not the world, but a statistic from a relatively narrow segment of the internet should not be assumed representative of the whole.

In the US, stove burners are rated in the confusing units of “BTUs” which is actually a unit of energy, not power. When they say BTU, they mean BTU/hour. The highest-rated burners on a typical stove are about 10,000 Btu (per hour), but high-end stoves can get up to about 18000 - that is equivalent to about 5000 watts. My single-element induction top is only rated for about 1000 watts. So although it heats and cools rapidly, I suspect it is not up to the demands of wok cooking (unless one wants to cook only very small portions).

not Chinese, but I cook a lot with a wok. I also have a single induction cooktop and surprisingly, the wok has enough iron to work with it while some old cheap conventional cookware did not. However, wok cooking needs to be hot all over the wok and not just in that little point where the wok is close enough to the induction coil.

I have a conventional propane stove which I need to keep, because here in Puerto Rico the power system is quite unreliable (especially during a bad hurricane year). But the conventional stove burners are not really hot enough. With a 1/16 - inch drill bit I could increase one of the burners capacity substantially. I painted the stove knob red so people have some warning when they light that burner! It burns more gas, but wok cooking is really fast, so in the long run it is probably more efficient than lots of other cooking approaches.

I would definitely consider a wok-shaped induction heater. Induction heating is quite remarkable.

I have heard this, and I can imagine it is true, but have you seen any analysis? There must be a large crew traveling and lots of equipment - transportation is a big user of petroleum in general – for entertainment. Though they say the entertainment is good.

Swimming pools are normally constructed empty. They were withstanding surrounding soil before they were filled, and concrete strength increases with age (for about 90 days, typically). On the other hand, a sunken structure like a pool that is roofed over, becomes a “confined space”. Unlike a typical structure, heavier-than-air gases cannot escape from the pool. Such gases could originate from the drain system or flow from leakage outside the pool area. For examples, leaking propane or various gases from sewer lines in the vicinity. A sunken greenhouse would almost certainly be a building code violation for that reason. If you build it, ventilate it by means both active and passive and do not enter if you can’t verify that ventilation is working.

top slab is about 230 or 240 pounds. Wood base is only about 15 or so; light. I made no attachment between the concrete and the wood - just gravity.

How often in the software industry is the title “engineer” a sop to give applicants a flashy title; and how often is there actual engineering involved? When I worked as an engineer some years ago, it seemed inconceivable that software development would become actual engineering because how could the engineering standards of care and professional liability ever be imposed? Today, virtually all software is either privately licensed or open source - there is no such thing as public software infrastructure under the development supervision of a professional software engineer (as far as I know). So I guess Mozilla can call their software developers anything they like, but it seems to be an ongoing cheapening of the engineering title - like why not call this position Chief of Software Surgery? Lead Software Counselor?

Engineers describe heat transfer with a “heat transfer coefficient”, and the rate of heat transfer is this coefficient multiplied by the temperature difference. So you can calculate what the heat transfer coefficient must be by measuring room air temperature initially, water temperature initially, and then running your system for a little while and measuring the room temperature again. The smaller room area you can cool the more accurate this will be. You will need to look up heat capacity and density of air (easy to find), and the temperature change of the air with the volume of the room and the temperature change will together give you an amount of heat you removed from the air to the water. Simple!

If you think about it though, coming into a kitchen and saying “it smells good!” is OK; if the odor is bad, maybe lack of carbon filter is not the problem! lolz I have a recirculating fan, but I don’t think it does much odor trapping. Odor molecules come in all sorts of forms - some adsorb to carbon and some don’t. Although activated carbon has a large capacity considering the size of the particles of carbon, it can’t do miracles. Furthermore, I suspect the carbon is encased in trapped oil long before its odor-absorbing capacity is exhausted (though I guess that depends on one’s cooking style).

I am not sure if that is the same; the assembly on the solar panel was larger diameter than the rest of the piping system perhaps around the size of a two-inch PVC ball valve, where the rest of system was (if I recall right) about 1-inch or maybe 1.5? But I guess there could have been a component like this inside. I am familiar with these for automotive thermostats in cooling systems, but I never pictured that they might have meant this. Otoh, why not? It would do the job and maybe work for OP’s project; especially if they are made for a range of different temperature conditions.

I used to have a solar water heater for my swimming pool, and it had a wax-actuated valve (!) When the water in the panels was hot enough to melt the wax, a paddle could start turning, and water could flow in the panels. If the water cooled, the wax would congeal and the paddle would “freeze” - blocking water flow - the pool circulating pump had a pressure regulating valve and relief valve, so when the panels on the roof were not accepting water, the pump would bypass them and deliver water straight to the pool without heating. I thought it was quite clever (the wax and paddle assembly were inside a sealed device - I never actually saw how it functioned, only recall the vendor explanation). I have not seen a comparable invention in several internet searches over the years.

whatever does not kill us, makes us stronger? LOL I think it might be OK if you rinse it very thoroughly - in a way it might be like beer-brewing. In olden times, the quality of water was not easy to assess - it might make you sick. But beer, if it tastes good, is proof that conditions have been achieved for fermentation and therefore, bacteria could not be present in significant numbers (else the beer would sour!). Maybe a healthy spirulina population in a pond is like that? I suspect it is true, but I have been unable to develop a spirulina culture so far (and partly from lack of serious effort).

I watched some youtube videos about people growing spirulina in backyard pools. They tell all about how to do it. One guy says normally he would dry it to powder and add it to “regular” foods. But he sometimes just eats it as-collected. It has no taste, or sometimes a faintly “fishy” taste

The issue with marine algae is not mercury, but arsenic. We know inorganic arsenic is toxic, but marine algae accumulate arsenic in organic molecules, which some studies seem to show that is less toxic or even non-toxic. But some effects of arsenic toxicity are long term, like cancer, and apparently it is not a decided issue yet. There has been arsenic in the sea for a long time, and marine creatures of all sorts have evolved to deal with it in various ways.

yep, these are all marine algae. I think the market will develop and more consistent products (and no doubt thorougly coated with preservatives) will become prevalent once dear old General Mills, ConAgra, and their like enter the fray.

This could be for marine algae, which might have high iodine and sometimes high organic arsenic (though there is some debate over how toxic that is) - but freshwater algae are not necessarily high in iodine. Like spirulina for example.

I built it to fit some glass that was about the right size, so not really a design others would emulate precisely. But a standard sheet of galvanized sheet metal is about three feet by six feet, so four 10-foot boards will nicely make the “box”. I used 1x2 for the corner bracings (just glued and screwed), window frames, and dryer trays. I had made an earlier version with a sheet of translucent corrugated roofing for the lid, and that heated up quite well, too. The legs were just some scrap - I think the angle of the box should be around 45 to achieve some natural convection and good mid-day sun collection area. But it could vary with one’s latitude I suppose - in a more northern clime (I’m at 20N), a more vertical “cabinet” might work - the dryer trays would be shallower, but convection would be better. I am not sure the vent stack makes any difference.

I rotated 90 right and the picture was 180 from OP, so I rotated back 90 left and tadaa:

I tried disabling Privacy Badger - that sometimes interferes - but no help

I guess, but cannot tell for sure; I did not rotate the pic from the time I took it until I posted. One can “preview” a post, but once you click preview you cannot back up to make edits (at least with my configuration - Firefox on Ubuntu Linux) - browser back button does not work. A mystery!