How Cyprus Became a World Leader In Solar Heating (theguardian.com) 104
The republic of Cyprus "has outstripped all other EU member states in embracing hot-water solar systems," reports the Guardian, "with an estimated 93.5 % of households exploiting the alternative energy form for domestic needs."
EU figures show the eastern Mediterranean island exceeding renewable energy targets set in the heating and cooling of buildings thanks to the widespread use of the solar thermal technology... [First introduced in the late 1960s], the solar thermal systems not only collected solar energy as heat — usually generated through electricity and the burning of fossil fuels — they were extremely cost-effective and had helped spawn an entire industry [says Charalampos Theopemptou, the island's first environment commissioner and the head of the Cypriot parliament's environment committee].
"It's been great for low-income families and then there's the jobs: so many have been generated," the MP says. "There are the local manufacturers who produce the parts and then all the people who are trained to install them. It's big business." In his role as environment commissioner, Theopemptou pushed hard to make the solar systems obligatory on all newly constructed residential and commercial buildings... The popularity of the water heaters is such that a union of local solar thermal industrialists was established in 1977. Since then, more than 962,564 square cubic metres of "solar [panel] collectors" have been installed, the union says. Increasingly, the country's vibrant tourist industry has also resorted to the green solution with solar-powered hot water systems deployed in, they say, close to 100% of hotels...
For Demetra Asprou, a retired engineer, it's obvious that a region blessed with more than 300 days of sunshine a year should embrace solar energy. "It reduces electricity costs, increases the efficiency with which hot water is provided and is kind to the environment," she says. "Why would anyone use other, more traditional means to heat up water when only a few hours of sunlight, between 11am and 2pm, is enough for a 200-litre [44-gallon] tank to be filled with warm water that will last 48 hours? On days when there is no sunlight, which is rare, you always have electricity as a backup if necessary... Installation costs may be three times higher today, but there are EU-funded grants that the government hands out and within a year it's all paid off," she says. "After that, you basically have free hot water and see your electricity bills greatly reduced. In a country like Cyprus, it's a no-brainer."
Thanks to Slashdot reader votsalo for sharing the article.
"It's been great for low-income families and then there's the jobs: so many have been generated," the MP says. "There are the local manufacturers who produce the parts and then all the people who are trained to install them. It's big business." In his role as environment commissioner, Theopemptou pushed hard to make the solar systems obligatory on all newly constructed residential and commercial buildings... The popularity of the water heaters is such that a union of local solar thermal industrialists was established in 1977. Since then, more than 962,564 square cubic metres of "solar [panel] collectors" have been installed, the union says. Increasingly, the country's vibrant tourist industry has also resorted to the green solution with solar-powered hot water systems deployed in, they say, close to 100% of hotels...
For Demetra Asprou, a retired engineer, it's obvious that a region blessed with more than 300 days of sunshine a year should embrace solar energy. "It reduces electricity costs, increases the efficiency with which hot water is provided and is kind to the environment," she says. "Why would anyone use other, more traditional means to heat up water when only a few hours of sunlight, between 11am and 2pm, is enough for a 200-litre [44-gallon] tank to be filled with warm water that will last 48 hours? On days when there is no sunlight, which is rare, you always have electricity as a backup if necessary... Installation costs may be three times higher today, but there are EU-funded grants that the government hands out and within a year it's all paid off," she says. "After that, you basically have free hot water and see your electricity bills greatly reduced. In a country like Cyprus, it's a no-brainer."
Thanks to Slashdot reader votsalo for sharing the article.
WTF (Score:3, Insightful)
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five dimensional meters
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no - six.
Re:WTF (Score:4, Informative)
When you square a linear measurement, you add another axis taking it from describing segment of line to a segment of a plane.
It follows that if you have a three dimensional measurement and 'square' it, you only have to add one additional dimension orthagonal to first three.
Therefore a squared square would be a cube, and a squared cubic meter would be a hypercube of four dimensions.
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(x^y)^z = x^(y*z)
"adding one dimension" would be an increase by 1 of the exponent.
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Re: WTF (Score:3)
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meter and metre is the same.
Just different spelling based on language.
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I am not confused.
Both is the same.
Same as with liter and litre :P
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Well if we had that... (Score:1)
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Uh .. live in California .. pretty sure most of this state has that. Also multiple other states have that .. if solar'd a few dozen square miles of Arizona or New Mexico, and made corresponding distributed battery banks, we could power the whole USA with solar. Reference: https://landartgenerator.org/b... [landartgenerator.org]
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More like around 8900 square miles to provide all the electrical power for the US. A bit more than a few dozen. That's a little under 8% of Arizona. A pretty big area, but doable. On the other hand, if you wanted to replace all energy usage. That means all electricity, but also all oil, coal, natural gas and anything else combined, you would need about 61,000 square miles of solar panels. That gets a little tricky though, because if you replaced all that with electricity, there would probably be significant
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P.S. The numbers I provided are assuming an average of about 20 Watts per square meter, which is around the range a good solar farm typically works out to. That may seem low, but peak sunlight for solar power only lasts a small part of the day. when you consider 1000 Watts per square meter on a perfect day and a solar panel efficiency of about 20% and divide by the fraction of time during the day it will produce peak power, that's about what it works out to. Now, if we can get 40% efficient solar panels, w
One line answer - Government mandates (Score:2)
Skeptical of these 2 fact + 2 person's quotations shovel ready news stories. Just report the 2 lines lots of sunny days and mandated by government law.
Have to read about a thousand words before the "mandated by government laws" comes in.
>In his role as environment commissioner, Theopemptou pushed hard to make the solar systems obligatory on all newly constructed residential and commercial buildings – a move instituted by Israel back in the 1970s.
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There are lots of laws to
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Sunny countries with lots of sun use the sun (Score:5, Informative)
Cyprus is a sunny country with 320 days of sunshine and an arid climate with few clouds.
It should surprise no one that water heaters make more sense there than in, say, Finland.
Also, electricity is 34 euros/kwh in Cyprus.
Warm, sunny countries all over the world use solar water heaters.
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1) Move your entire country as far south as you practically can.
2) ???
3) Profit!
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34 Euros per kWh is ridiculous. Seems like they have some work to do.
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Whenever I hear numbers on cost per kWh somewhere, I always wonder if that's the delivered cost or not. In a lot of places, delivery charges can be just as high as supply charges.
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Hopefully so! 0.34 Euros per kWh is cheaper than some parts of the US. 34 Euros per kWh means that anyone able to import solar panels would be incredibly wealthy.
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That's likely because of all of the solar panels, because they need to subsidize spinning reserve + night power if they have too many. Because of its location, Cyprus is not meaningfully interconnected, and so it has to actually produce the power itself rather than be like Denmark and pretend to have a self sufficient grid while outsourcing its maintenance to Norwegian and Swedish hydropower. This is why their official renewable numbers are low in spite of a lot of solar panels installed which you'll see if
Re:Sunny countries with lots of sun use the sun (Score:4, Informative)
Also, don't forget that it means substantial reductions in electricity demand at peak times, i.e. mornings & evenings, when people tend to use a lot of hot water. The hot/warm water is stored during the day to be used at those times. Therefore photovoltaic & battery systems will have substantially lower demand at these times because fewer people are heating water with electricity. Even in climates & in seasons where/when the water doesn't get very hot, it still reduces the energy needed to make it hot. The technology is so simple & cheap, & saves so much energy that it's a no-brainer to install.
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I was talking about the reason for high electricity prices. Granted since you thought this is about Crete in this same thread, I'm not surprised you didn't notice the subject being high electricity prices on the Greek side of the island.
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The only relationship solar water heaters have with electricity is that they make you use less of it for heating water. Apart from that, there's no electricity involved.
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>Are you confusing it with Cyprus?
Yes, I'm totally the one confusing it.
On a completely different topic, have you read the headline of this page yet?
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Photovoltaics don't cost 34 Euros per kWh.
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Backing them up without interconnects to significant dispatchable producers on the other hand does cost that and more.
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You have some work to do.
The less electricity the population uses, the higher the price per kW/h.
As the costs for the grid/infrastructure is a fixed cost.
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For those who don't know what a "solar water heater" is, it's a water tank on the roof of a building that's painted black.
The main problem with them is weight. Water is heavy. You need to overprovision the building carrying capacity by a significant margin to mount water tank on top of it safely. One of the biggest emitters of CO2 is concrete manufacturing. So you shouldn't do this unless you live in a very dry and sunny climate that is otherwise fairly hot in terms of outside temperatures (no need for acti
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For those who don't know what a "solar water heater" is, it's a water tank on the roof of a building that's painted black.
No, it really isn't. The tank is only up there so you don't have to spend energy pumping water up from a tank at ground level. The heater itself is a flat surface, not unlike a PV panel, that has pipes running across it through which water is circulated. You can either use pumps or creative plumbing (e.g. a thermosiphon) to keep the water flowing.
Just sticking a big tank up there would be stupidly ineffective thanks to the square-cube law. That's not to say no-one does it this way - it's much simpler and he
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Visit Cyprus sometime. You'll find all those "inefficient and cheap" solutions, and very few of the "efficient and expensive" ones.
The reason they do this is that island is fairly poor by Western standards, but has the optimal climate for just mounting a big barrel shaped tank on the roof, painting it black and using it as a water heater.
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Literally clicking on the article and just looking at the picture in the banner (a picture from Cyprus) shows how wrong you are. Doubling down just makes you twice as wrong.
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Crete is basically a giant holiday resort, an ancient Greek outdoor museum, & has some typically high-quality agriculture, e.g. organic olive oil. A lot of ex-pats retire or work remotely from there or have holiday homes there too. It's more at the middle to luxury end of living conditions than you seem to believe.
Re: Sunny countries with lots of sun use the sun (Score:2)
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BTW, Cyprus is a higher-income country than Greece/Crete. They're also sitting on massive natural gas reserves, they're a major shipping hub, & do a lot of dodgy banking for billionaires, oligarchs, corporations, etc..
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Indeed. Crete is much nicer in fact, in large part due to being much further away from Anatolia. So it's not occupied, and doesn't have to burn a lot of resources just maintaining status quo vis a vis hostile Turkey.
Not to mention being much further away from European mainland, so much more isolated in terms of cabling and such.
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It does. You appear to confuse "wealth of citizenry" with GDP however.
Whereas Cyprus is one of many nations that demonstrate that one does not in fact correlate well with the other unless very specific conditions are met.
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So you shouldn't do this unless you live in a very dry and sunny climate that is otherwise fairly hot in terms of outside temperatures
That's like, 90+% of Australia. No wonder solar is so popular here.
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Yup. And they're great in Maldives. Or was it Madagascar?
Well, it's not like you can tell the difference.
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For those who don't know what a "solar water heater" is, it's a water tank on the roof of a building that's painted black.
There certainly are people here who don't know what solar water heaters are, but it would seem that this person is you. Ironically enough the tank on the roof is one component that is neither black, nor has any function in heating.
The main problem with them is weight. Water is heavy. You need to overprovision the building carrying capacity by a significant margin to mount water tank on top of it safely.
No it's not. Most roof constructions can handle a solar hot water system. These things have been retrofitted in buildings without additional support the world over. Sure if you're a 3rd world country and you build your roof from straw than this isn't for you, but spoiler alert: th
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>Most roof constructions can handle a solar hot water system.
How much is "most", and where is this "most"?
Because Med construction in general is built in a very specific, fairly old and notably corrupt way that tends to lead to cut corners in places where they know from experience they can, but that leads to long term problems. So when you do actual structural analysis to retrofit a heavy water tank on top of such buildings, you generally have to do a load bearing assessment.
And then reinforce the buildi
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BTW, if you look at photos of them, you'll notice that the water tanks are painted white & insulated to stop the water from overheating & keep the water hot overnight, when the temperature drops & the sun isn't shining. The part that heats the water is a large rectangular panel that looks a bit like a solar pa
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The tanks on the roof have nothing to do with hot water.
They are there that if there is a power failure, aka the pumps do not work, that you still have water from the tap.
The hot water is a 100l to 200l small tank, integrated into the heater.
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Re: Sunny countries with lots of sun use the sun (Score:2)
The main problem with them is weight.
Not really a problem. I have a 40 gallon tank on the second floor of my house. No extra framing was required. Putting it on the roof would have been trivial.
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Look up the typical construction standards and styles on Greek (culturally) islands. You'll understand why it's not, and why quite a few of those buildings needed to be reinforced.
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Brick, stone and stucco. Heavy timber framing to hold up very heavy tile roofs. I don't think a hot water tank would make a difference.
I've stayed in a number of Greek houses. Very heavy and thick to moderate the interior temperatures.
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Yup. Lots of heavy non-load bearing walls on timber frame.
What could go wrong if you just slap some extra weight on it?
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They do in fact have solar heating systems in Finland. They work between February and November, so most of the year. Solar heating works even on dull days, just not as effectively.
The real question you need to ask is if it is better suited than putting solar PV on your roof. You can calculate the savings from both, for different types of electric water heating (resistive, heat pump), based on where you live. You can of course have both if you have the space.
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Cyprus is a sunny country with 320 days of sunshine and an arid climate with few clouds.
It should surprise no one that water heaters make more sense there than in, say, Finland.
Also, electricity is 34 euros/kwh in Cyprus.
Warm, sunny countries all over the world use solar water heaters.
Came here to say that, lol. Heating things in Cyprus is not generally a problem.
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It should surprise no one that water heaters make more sense there than in, say, Finland.
Their numbers are weird. Almost the entire Middle East has water tanks on top of their roofs for hot water. How does Cyprus end up being singled out here?
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Electricity isn't 34 euros/kwh in Cyprus https://countryeconomy.com/ene... [countryeconomy.com]
Also these heaters work in winter when it's cold and, less well, even when cloudy. Worst case, you fall back to whatever other heater.
Lots of sunny sunny countries do not, in fact, use these solar heaters as much as they could be.
Ripped mine out recently (Score:5, Interesting)
I am in a sunny spot and the system worked great for ~14 years. Then it leaked. Replacing it was about 5x the cost of a heat pump unit, so I went the HPWH route. A single 100W solar panel is enough to offset its energy use on an annual basis; a 400W panel and 12V/100Ah battery could run it off-grid year-round.
THIS (Score:2)
PV + heat pump economically outperform thermal solar any (sunny) day now.
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Indeed I think solar thermal will be replaced by PV, eventually, but the economics between the two technologies differ wildly across countries.
You must be in the U.S. where it costs ~$10K to install a solar thermal water heater.
You can get a good quality 160L solar water heater installed in Greece for about 1000 EUR. It must be similar in Cyprus. How much does it cost to install the 400W panel + 12V/100Ah battery + heat pump water heater in the U.S.?
The PV system is much more versatile, because you can us
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FCUs for cooling are common in Southern European countries too, at which point you already have the heatpump.
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Some prefer not to have the walls hung with a bunch of externals and multisplits aren't cheap either. You don't need anything specialized, pretty much all air to water heatpumps can do heating, cooling and supplying hot water for a boiler heat exchanger (not all at the same time, so when it's heating up the boiler, heating/cooling is suspended unless you have a massive parallel buffer tank, a small compromise).
Italy especially has a large amount of heat pump and FCU manufacturers. Because of the traditional
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The cost issue seems to be that some countries just don't install enough of them to get economy of scale. A basic system starts at 500 Euro installed in some places. Certainly shouldn't cost 5x what a HPWH does.
For a lot of people though, solar PV is probably the way to go. If your country is moving away from gas boilers anyway then you will need a heat pump at some point anyway.
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"Replacing it was about 5x the cost of a heat pump unit"
The components of a hot-water solar system are a subset of the components of a heat pump. You can even make a hot-water solar system yourself out of parts from a hardware store. (I have an uncle who actually did this, and he doesn't live in Cyprus.)
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I made one from 200m long black plastic hose.
Holds 60 liters. Enough to shower 5 to 6 minutes if you like to shower really hot.
About $20.
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Yes, you can DIY them cheap. You can also shower with cold water for cheap. The problem here is I cannot DIY plumbing work, and plumber and helper charge a day rate of about $2,000 plus 100% markup on parts. But, 5x the cost is based on a professional installation and warrantied equipment of comparable function.
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You do not need any plumping, to make a hot water solar shower from a black hose.
Why can't we? (Score:2)
Why can't we double down on solar? You realize that once you spend the capital expenditure to get solar, well water, EV, and a house. Your family can live while you're virtually jobless? There'll be no such thing as an economic downturn as you can live on savings of a few hundred bucks a month (mostly for internet/Starlink), and maybe food if you don't wanna grow your own food (possible in most of the US if you have 2 acres). You only need to get (free) Obamacare and life insurance for your family. Public s
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I think I understand what you mean, but this idea of being "virtually jobless" suggests that farming and teaching aren't jobs...
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Something that is not compensated by money, is not a job :P
If you do not lime gardening/farming - then just don't do it.
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Yeah, I dunno about the whole off grid-but, but I do agree with the overall principle. I want the US at least to go bonkers on solar, and wind, nuclear too if people could get their . I really, really do not understand this fetish with oil ("energy" if you believe the petroleum propagandist lobby). If we can max out renewables, then we don't have to deal with these gawd-awful petrostates. Russia, Saudi Arabia, Venezuela, Iran, Iraq, Texas (jk) , the list goes on.
Even though the US produces a ton of the
Cyprus? Try Israel (Score:2)
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Yeah.
>> Cyprus is doing this thing.
> No, Israel does it!!!
How odd.
Lovely (Score:2)
If only their banks worked so well.
ignorance is a bliss (Score:1)
It's pretty much the same in Greece (Score:3)
It's pretty much the same in Greece, as it should be for any country with significant sunshine. The total percentage might have fallen after the recession for new homes (I am just guessing as people are cutting corners), but basically you pay 600 to 1200 euros once and then have free hot water for 20-25 years. They have an electric backup, but you only need to switch that on just a handful of times per year in my experience - it basically requires a couple of very overcast days. They usually use 120-200L tanks, so you don't have an unlimited quantity like you would with a boiler, so you use it a bit differently than that, but if you grow up with it, it does not feel like a serious limitation.
back in the 90's (Score:2)
True story
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These tanks are strange... (Score:2)
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How can such a large lid withstand the pressure of the water system (several bars), and what is it for?
Each system also has a narrow vertical pipe that reaches higher than the top of the tank. Is it some kind of pressure-release valve?/quote]
It's the fill pipe.
Water is pumped into the top tank, and drawn from the bottom tank. It circulates between the heater panels and the bottom tank, while the top tank provides a reliable supply of fill water.
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Next thing they need ... (Score:2)
Practically everyone on the Greek islands has AC. And power (usually from grid-sized diesel generation) is expensive.
And I have, right there on my bookshelf... (Score:2)
...a book from the seventies on how to build your own solar water heater/prewarmer. And, if need be, you can feed the output of your rooftop solar water heater into your ordinary water heater.
And, um, er, those of you critical of this, tell me, ever get a sunburn on a cloudy day? Are you under the mistaken impression that IR doesn't get through the clouds?