Keeping Thermal Plants Cool Without Breaking The Cooling Water Budget

Steam generators in thermal (steam-cycle) power plants require a constant influx of cool water to maximize the transfer of thermal energy. How this water is cooled again in the condensor after much of the steam’s thermal energy has been spent in the steam turbines or heat exchangers is a very important consideration in the design and construction of these plants. The most obvious and straightforward system is direct “once-through” cooling, where the water is drawn straight from a nearby river or other body of water and released after passing through the condenser. This type of system is by far the cheapest, but is also impacted by both the seasons and environmental considerations.

Where cool surface water is less abundantly available, evaporative cooling in a recirculating system such as with spray ponds and cooling towers is a good alternative. Although slightly more costly, a big benefit of these is that they require far less water and have much more control over the intake water temperature, which can raise plant efficiency. Finally, dry cooling is essentially a closed-loop system, which is exceedingly useful in areas where water is scarce. This latter type of cooling is what allows thermal plants to operate even in desert regions.

As the global climate changes – with more extreme weather events – picking the right cooling solution is more important than ever, and has us looking at retrofitting existing thermal plants with more efficient solutions. If you were ever curious how power plants keep the cool side cool, read on!

Continue reading “Keeping Thermal Plants Cool Without Breaking The Cooling Water Budget”

Know Snow: Monitoring Snowpack With The SNOTEL Network

With summer just underway here in North America, it may seem like a strange time to talk about snow. But when you live in North Idaho, winter is never very far away and is always very much on everyone’s mind. Our summers are fierce but all too brief, so starting around September, most of us begin to cast a wary eye at the peaks of the Bitterroot range in the mornings, looking for the first signs of snow. And in the late spring, we do much the same, except longingly looking for the first signs that the snowpack is finally breaking up.

We all know how important snow is, of course. Snow is our lifeline, nearly the only source of drinking water we have here, as well as the foundation of our outdoor recreation industries. We also know that the snowpack determines our risk for wildfires, so while the long, dark winters may take a psychological toll, the longer the snow stays on the mountains, the less chance we have of burning come summer.

These are all very subjective measures, though, and there’s way too much riding on the snowpack to leave it up to casual observation. To make things more quantitative, the US Department of Agriculture’s Natural Resources Conservation Service (NRCS) has built a system across the western US that measures the snowpack in real-time, and provides invaluable data to climatologists, fish and game managers, farmers, and even the recreation industry, all of whom have a vested interest in the water held within. The network is called SNOTEL, and I recently got a chance to take a field trip with a hydrologist and get an up-close look at how it works.

Continue reading “Know Snow: Monitoring Snowpack With The SNOTEL Network”

Wind-to-Heat: A Lot Of Hot Air?

Heating is one of the greatest uses of energy in human society today. Where we once burned logs to stave off the brutal winter chill, now we lean on gas and electricity to warm our homes and keep us safe and toasty. In some colder climates, like the UK, heating can make up 60-80% of total domestic energy demands.

However, there are alternative ways to provide heating. Using wind energy to directly provide heat could be key in this area, using a variety of interesting methods that could have some unique niche applications.

Continue reading “Wind-to-Heat: A Lot Of Hot Air?”

3D Printed Machine Shows How Braiding Is Done

If there’s something more fascinating than watching cleverly engineered industrial machines do their work, we don’t know what it could be. And at the top of that list has to be the machines that do braiding. You’ve probably seen them, with spools of thread or wire dancing under and around each other in an endless ballet that somehow manages to weave a perfect braid. It’s kind of magical.

For those who haven’t seen such a thing, now’s your chance, with this twelve-spool braiding machine. The building methods that [Fraens] used — mainly 3D printing and laser-cut acrylic — make the workings on this machine plain, even to those of us who never learned to manually braid even three strands. It’s far easier to understand by watching the video below than by trying to describe it, but basically, each vertical supply spool runs along a continuous track around a central point by a series of six meshed gears, passing under each other as they progress around the carousel and forming the braid.

There are a ton of details that go into making this work. Chief among them is the thread tensioning mechanism, which is a lever arm and spring-loaded axle that lives at the very center of each spool. The gears that form the inside-outside tracks are quite clever too, as are the worm-gear-driven takeup reel and output tensioner. We also appreciated the gate used to load the spool carriers into the track.

We can recall a couple of braiding machines before, including this one made entirely from Lego Technics.

Continue reading “3D Printed Machine Shows How Braiding Is Done”

Radio Apocalypse: Hardening AM Radio Against Disasters

If you’ve been car shopping lately, or even if you’ve just been paying attention to the news, you’ll probably be at least somewhat familiar with the kerfuffle over AM radio. The idea is that in these days of podcasts and streaming music, plain-old amplitude modulated radio is becoming increasingly irrelevant as a medium of mass communication, to the point that automakers are dropping support for it from their infotainment systems.

The threat of federal legislation seems to have tapped the brakes on the anti-AM bandwagon, at least for now. One can debate the pros and cons, but the most interesting tidbit to fall out of this whole thing is one of the strongest arguments for keeping the ability to receive AM in cars: emergency communications. It turns out that about 75 stations, most of them in the AM band, cover about 90% of the US population. This makes AM such a vital tool during times of emergency that the federal government has embarked on a serious program to ensure its survivability in the face of disaster.

Continue reading “Radio Apocalypse: Hardening AM Radio Against Disasters”

Learning 3D Printing Best Practices From A Pro

It might seem like 3D printing is a thoroughly modern technology, but the fact is, it’s been used in the industry for decades. The only thing that’s really new is that the printers have become cheap and small enough for folks like us to buy one and plop it on our workbench. So why not take advantage of all that knowledge accumulated by those who’ve been working in the 3D printing field, more accurately referred to as additive manufacturing, since before MakerBot stopped making wooden printers?

That’s why we asked Eric Utley, an applications engineer with Protolabs, to stop by the Hack Chat this week. With over 15 years of experience in additive manufacturing, it’s fair to say he’s seen the technology go through some pretty big changes. Hes worked on everything from the classic stereolithography (SLA) to the newer Multi Jet Fusion (MJF) printers, with a recent focus on printing in metals such as Inconel and aluminum. Compared to the sort of 3D printers he’s worked with, we’re basically playing with hot, semi-melted, LEGOs — but that doesn’t mean some of the lessons he’s learned can’t be applied at the hobbyist level. Continue reading “Learning 3D Printing Best Practices From A Pro”

Smoke Some Weeds: Lasers Could Make Herbicide Obsolete

We’ve all tangled with unwelcome plant life at one point or another. Whether crabgrass infested your lawn, or you were put on weeding duty in your grandfather’s rose patch, you’ll know they’re a pain to remove, and a pain to prevent. For farmers, just imagine the same problem, but scaled up to cover thousands of acres.

Dealing with weeds typically involves harsh chemicals or excessive manual labor. Lasers could prove to be a new tool in the fight against this scourge, however, as covered by the BBC.

Continue reading “Smoke Some Weeds: Lasers Could Make Herbicide Obsolete”