CR4® - The Engineer's Place for News and Discussion®



TechnoTourist’s Engineering Expeditions

Want to travel the world, but don't have time to leave the office? TechnoTourist is here to save the day! Tag along while TechnoTourist visits famous engineering feats around the world. TechnoTourist will also investigate fascinating technologies that help to preserve and discover incredible travel locations. Maybe you could use TechnoTourist's insights to help you plan your next travel itinerary, or escape from the stresses of everyday life!

Solar Power in Greece: Stalled but not Out of Gas

Posted December 19, 2017 11:23 AM by BestInShow
Pathfinder Tags: Greece solar power

As we passed through residential suburbs on the way from the airport to downtown Athens, I noticed that many of the rooftops sported solar hot water tanks. Given the amount of sun – the Athens area has around 2700 hours of sun a year – the use of solar energy isn’t surprising. Many of the Greek Aegean islands are little more than rocky crags poking up from the sea, with few, if any, resources to provide electric power. Solar-powered electricity generation is especially appropriate for such locations.

So I was surprised to learn that, while Greece was a photoelectric pioneer, now the country lags behind other EU members. Renewables provide 20 percent of Greece’s electricity. An internet search reveals that the peninsula has plenty of solar equipment manufacturers and installers, yet the impetus to expand the installed base of photoelectric generation and distribution is flagging. And new lignite-burning electricity generation plants are coming online.

The Great Leap Backward

The reasons for this seeming leap backward? Some analysts point to tradition: Greece has long used lignite (a low-quality coal) to produce electricity. Greeks accept that the stuff pollutes the air and costs money but because lignite is mined within the country, using it means energy self-sufficiency and job creation. "Lignite helped develop Greece after World War II," says Lefteris Ioannidis, mayor of the municipality of Kozani, the epicenter of coal country. "It was cheap, accessible fuel that helped everybody here get jobs with good salaries. And this region, all of Greece, really, got addicted to it. It's been hard to change that."

An advocate for bringing wind power to Greece’s Aegean islands, Yiannis Tsipouridis, has made some modest progress. He has also heard some far-out excuses: wind turbines cause miscarriages, they chase away clouds. These remind me of some of the stuff my grandmother used to say like the moon landing never happened and the pictures came from a stage set.

European Union regulations are another contributing factor. The EU promotes the development of alternative and renewable energy sources, yet new regulations inadvertently discourage the extension of photoelectric generation, at least in Greece. Both Thessaloniki and Larisa, cities in northern and central Greece, respectively, have installed photoelectric systems on public building rooftops. When a given installation generates excess power, the excess can be credited to another public building that uses a lot of energy. Proposed changes to the EU’s Renewable Energy Directive, will require selling excess energy back to the grid, rather than “re-route” it. The Greek model, called virtual net metering, would kill the successful projects already operating in Thessaloniki and Larisa.

A Model for the Future?

Despite these setbacks, one Greek island is cutting the electric cord, metaphorically speaking. The Dodecanese island Tilos used to receive power via an underwater cable from Kos, an island about 25 miles north of Tilos that produces oil-based electricity. In September 2017, Tilos embarked on a pilot project to generate enough electricity for its small – fewer than 800 people during the summer – population by using renewable sources. The European Commission is providing most of the funding for this €15m experiment, which comprises one wind turbine and one small photovoltaic park. A residents’ association is also supporting the project. Tourism on Telos is growing modestly, driven in part by interest in the clean-energy experiment.

New large-scale generating plants are also opening with more on the way. Hellenic Petroleum, which, as its name suggests, primarily focuses on refining and trading petroleum products, had just added 8.6 megawatts of photovoltaic capacity. The company intends to continue its expansion into PV, taking advantage of Greece’s revised renewable energy law that provides incentives like virtual net metering.

Tradition can put up substantial barriers to change, even when proponents of doing things we’ve always done them acknowledge that the new way is better. If Greece can overcome unfavorable EU regulations, and encourage its citizens that wind turbines really do not chase away rain clouds, the country could get back to its pioneering adoption of renewable energy generation.

Image credits:

Livadia harbor on Tilos. Kostas Limitsios/flickr CC BY2.0

Solar power plant on the Island Tilos (Greece). Ulrich Scherf/Wikimedia Commons CC BY-SA 4.0

Add a comment

Say It Isn't So! Greek Theater Acoustics Aren't Perfect

Posted November 15, 2017 9:55 AM by BestInShow
Pathfinder Tags: Epidaurus acoustics

Have you ever heard that Greek theaters, at least some of them, had such perfect acoustics that the audience could hear a word whispered from the orchestra all the way up in what we might now call the cheap seats? I’d read this claim. When our tour coordinator offered an excursion to Epidaurus, the best-preserved of all ancient Greek theaters, I whipped out my credit card and booked the trip.

The theater’s architect, Polykleitos the Younger, created an impressive structure that could hold between 13,000 and 14,000 spectators. The small surrounding territory of Epidauria is considered to be the birthplace of Apollo’s son Asclepius the Healer, the god of medicine. The area grew into the most revered place to go for cures for mortal ills. Over time the settlement grew to include extensive accommodations for pilgrims seeking health. In the fourth and third centuries BC, the prosperity brought by the shrine made construction of the theater possible. The structure is the best-preserved of extant ancient Greek theaters.

When we arrived at the theater, our tour guide suggested that we climb up to some of the higher tiers and listen while she made various noises from the orchestra center. She’d told us that the theater faces in the direction of the sea, so the sea breeze could help move sound toward the audience. According to two Georgia Tech researchers, the sea breeze had nothing to do with the acoustics; the limestone seats themselves perform the magic. The stone filters out low-frequency noise and reflects back the higher frequencies more typical of the human voice. The acoustical effect of thousands of human bodies sitting in those seats isn’t addressed, however.

When our guide demonstrated the acoustical magic, the effect wasn’t as advertised. Granted, my hearing isn’t what it used to be, but I wasn’t the only person disappointed. I’ve visited the whisper gallery in the US Capitol, and I’d hoped for something equally magical. I figured the fault was my perception and not the acoustics.

Just after our return, though, Mr. Best in Show read an article that debunked the myth of the Epidaurus theater’s perfect acoustics. Using techniques and equipment they developed themselves, a team from TU Eindhoven tested the acoustics of three Greek theaters, including Epidaurus, and proved conclusively that you can’t hear a whisper in the last row. The acoustics are very good, but not magic. These days the magic comes from performances that are held here, and in other ancient Greek theaters.

Photo credit: Flickr/Sharon Mollerus CC BY 2.0

33 comments; last comment on 12/11/2017
View/add comments

The Key to Power in Your Hotel Room

Posted November 10, 2017 10:44 AM by BestInShow
Pathfinder Tags: key card switch

On my recent trip to Greece I realized how well-trained I am to recycle stuff – soda cans, paper, plastic, stray bits of metal – when I couldn’t find any containers for these basic recyclables. Here and there at tourist sites I’d find a spot to dump a can. And at Athens International Airport the round waste receptacles are divided into thirds, with spots for paper, cans, and everything else. In general, though, I didn’t see much evidence that recycling is important.

However, all of the four hotels Mr. Best in Show and I stayed in had an energy-saving feature neither of us had encountered: a key card switch. Just inside the room door, there’s a small receptacle with a key-card slot. When the hotel guest inserts a key card, the power comes on. Before we knew about this marvelous invention, we thought our hotel in Athens had given us a dud room. A side benefit is that you always know the whereabouts of at least one key card.

After we got home I learned that these power-saving systems are common in European hotels. Since we stayed in apartments for our two previous European vacations, we didn’t know about them. And no US hotel or motel either of us had graced with our presence offered such a system. Why not?

Several sources I consulted estimate that energy costs soak up between four and six percent of a hotel’s total expenditures. Maybe US hoteliers don’t think the savings are worth the expense? Maybe guest comfort – and the sense that the guest controls her own environment -- are more important than saving money? Or are better systems in the offing?

The answer is a combination of these, and other, reasons. Nine years ago, Brian McGuinness, who at the time was a VP of Starwood Hotels and Resorts, explained that for hotel guests “part of being on the road means the ability to live a little more luxuriously than at home, and that means not having to turn off the lights and the TV.” Even upscale hotel brands like Starwood’s Element don’t have keycard switch systems.

Hotel owners also point out that key card switches are on the way out. Last year a retired Marriott executive said that more secure systems controlled by a guest’s cell phone will supplant key cards. Hotel rooms will also get smarter, relying on sensors that know when a room is occupied and thus in need of HVAC and live outlets for charging assorted devices.

Some US hotels, generally independently-run properties in older buildings, have found key card switch systems to be a good choice. Leviton, a Long Island-based manufacturer of key card systems, reports that system sales have increased 25 to 30 percent between 2014 and 2016. California’s tough energy standards are driving a big chunk of the increase, but other hoteliers are also fans. Guests by and large embrace the systems.

Unlike those we used in Greece, some systems allow guests to designate which circuits the cards control – so you can let your smartphone, e-reader, and laptop charge while you’re out of the room. Yeah, we finally realized that we had to have power to charge our stuff and we didn’t have power when we were out. We coped.

Image credit: Hotel key card holder. The holder contains a simple switch that will turn on the lights in the room. Photographed in Sokos Hotel Vaakuna in Mikkeli Finland. Public domain

19 comments; last comment on 11/22/2017
View/add comments

Driving a Moderately Smart Car in Greece

Posted November 03, 2017 8:00 AM by BestInShow

Driving in Greece is not for amateurs or the faint of heart. I learned this first-hand on a recent vacation with Mr. Best in Show. After a cruise through the Cyclades and the Dodecanese we rented a Toyota Auris hybrid and set off for Olympia, Delphi, and Kalambaka. Driving conditions--spectacular cloudless weather—could not have been better. The roads were in excellent condition, and signage included transliterated place name information. We were confident that our 1000-kilometer trek would be worry free.

Winding road in Crete. Photo credit: Maxpixel/CC0

However. Our previous driving experiences in Tuscany and Provence did not prepare us to share the road with drivers who generally treat "no passing" zones as challenges and speed limits as nonexistent. This, despite the fact that drivers—at least drivers who have properly-equipped cars—can’t claim ignorance at least about speed limits.

When I took over the driving I noticed a number below the graphic indicating whether the vehicle battery was charging or discharging. Sometimes the number showed as white on a red circle; other times it was red on white. Sometimes it disappeared altogether. Mr. BIS pointed out that this mystery number was the speed limit. Sure enough, our smart Auris somehow knew the speed limit.

The standard method for detecting speed limits is simple enough. An onboard camera scans the verge. When software recognizes a speed-limit sign, the numerical limit magically appears on the dashboard. Neural networks provide the intelligence. I had speculated that the sign itself was "broadcasting" the speed limit to a receiver in the car. The camera makes more sense. Toyota claims that its technology recognizes signs that comply with those approved by the Vienna Convention on Road Traffic. Yes, there is an international convention on road traffic. No, the United States is not a signatory; most of Europe and parts of Asia and South America have signed on.

The technology which makes this happen has been around for several years and was proposed in the first decade of the 21st century. Cars sold in Europe have this capability along with other components of an ADAS system. Since signs are standard, and the sign-reading cameras appear to be generally available, why didn’t our rentals (a Fiat and a Peugot in Italy and France) have this equipment? I ran across a couple of research articles about ADAS penned by Italian researchers, yet as far as I can tell, Italy does not require that cars sold in the country have any of these technologies.

Diagram showing how car-mounted camera captures speed-limit data. Photo credit: Toyota Global

After poking around a phenomenal trove of European Union documents on road safety, I failed to find any requirements for specific safety technologies. The EU did establish a 10-year plan to lower traffic fatality rates; participation by individual countries was essentially optional, however. About a year ago the European Commission distributed a document, "A European strategy on Cooperative Intelligent Transport Systems, a milestone towards cooperative, connected and automated mobility," that sets goals and standards for C-ITS, including specific services for "day 1" implementation—including in-vehicle signage and speed limits. The Commission has set 2019 as its goal for coordinated C-ITS deployment.

Back to Greece, where we found the in-vehicle speed limit displays very useful. Unfortunately, cars are not automatically slowed down to meet the standard. We also came within a gnat’s eyelash of a head-on collision with a speed demon who decided that the No Passing sign did not apply to him. Greek authorities admit that the main barriers to safer roads are lack of both traffic law enforcement and observance. Technology that slows down a speeding car, or stops one from passing two semis and a car in a no-passing zone on an undivided highway … probably not in the immediate future.

26 comments; last comment on 11/13/2017
View/add comments

A Piece of Ireland in Texas

Posted August 23, 2016 12:00 AM by joeymac

Everyone knows that kissing the Blarney Stone over in Ireland is supposed to give a person the gift of gab and eloquence of speech. I was fortunate enough to do this back in May earlier this year. Now here's something that most people don't know. A small chunk of the Blarney Stone resides at Texas Tech University.

The small chunk is cemented on the top of a small pedestal on the campus. The origins of this piece are mysterious. The stone was uncovered by a group of engineers near the campus in 1939. It was tested and was found to be identical with the original Blarney Stone in Ireland.

No one knows how it got there and there are rumors and legends about it just like the one in Ireland. On a side note that I thought was interesting, the Texas Tech Engineering Society has decreed that no Texas Tech underclass engineers can kiss the stone, so seniors only.

8 comments; last comment on 07/27/2017
View/add comments


Previous in Blog: Amsterdam's Canals  
Show all Blog Entries in this Blog

Advertisement