×

Welcome to the Slashdot Beta site -- learn more here. Use the link in the footer or click here to return to the Classic version of Slashdot.

Thank you!

Before you choose to head back to the Classic look of the site, we'd appreciate it if you share your thoughts on the Beta; your feedback is what drives our ongoing development.

Beta is different and we value you taking the time to try it out. Please take a look at the changes we've made in Beta and  learn more about it. Thanks for reading, and for making the site better!

More Data Centers Using On-Site Solar Power

timothy posted more than 2 years ago | from the be-my-little-sunshine dept.

Power 88

1sockchuck writes "Solar power hasn't been widely used in data centers because it takes a very large installation of photovoltaic solar panels to generate the levels of energy required by these facilities. But the month of April has seen the debut of four new data centers featuring on-site solar arrays."

cancel ×
This is a preview of your comment

No Comment Title Entered

Anonymous Coward 1 minute ago

No Comment Entered

88 comments

A Perfect Match (0)

phantomcircuit (938963) | more than 2 years ago | (#35997164)

Solar power is a perfect match for data centers. Their power demand is basically constant and they already have large batteries on site. So the main drawback of solar power isn't a problem for them (mostly).

Re:A Perfect Match (0)

Anonymous Coward | more than 2 years ago | (#35997228)

Over 12 hours worth of batteries intended to be drained completely on a daily basis?

(Honest question, I don't know myself).

Re:A Perfect Match (1)

phantomcircuit (938963) | more than 2 years ago | (#35997242)

They dont need to last for 12 hours, just long enough to make the transition to grid power.

Re:A Perfect Match (3, Informative)

thegarbz (1787294) | more than 2 years ago | (#35997442)

This is a roundabout way of going about it unless you power an entire datacentre off DC. Solar is typically stepped up via an inverter for larger operations, and the inverter syncs with the grid. Its actually kind of fun to watch our old analogue power meter stop spinning backwards and start spinning forwards when we turn the oven on and stop exporting power.

The transition between night and day should be perfectly seemless with no batteries required. These aren't diesel generators that we need to wait for, it's a grid, there's no sync delay and every Elec101 student should be able to design a system that seemlessly goes from export to import with no need for batteries.

That's not to say that there don't need to be batteries, but that switching to grid power is definitely not one of the reasons for them.

Re:A Perfect Match (0)

Anonymous Coward | more than 2 years ago | (#35997670)

I cant wait to see servers run directly off the native 12 volts they use internally from the power supply
allowing them to run more efficiently without the 80%-90% rating of up and down conversions

many switches, routers and specialized computers can already run direct DC for such installations

I always found it strange to
-Step the mains voltage down to the 12V for the UPS battery
-Then the UPS steps it up to 120/240V for the server PowerSupply Unit
-The power supply unit then to step it down to 12V for the mainboard and 6V for the components

two inefficient conversions of voltage

Re:A Perfect Match (1)

William-Ely (875237) | more than 2 years ago | (#35998626)

There's a reason for this. In large systems the need for a fast switch from utility to inverter power under full load requires that there be a battery charger constantly charging a battery bank and an inverter or rack of inverters connected to the battery bank to provide power to the load. This isn't very efficient but it works well.

Also battery voltage can vary from about 10 V to 14.4V per battery so I don't think this is tightly regulated enough for computer components. In a large system you want to keep the DC voltage high so your I^2*R power loss is minimalized so DC voltages as high as 108 V are not unheard of.

Re:A Perfect Match (1)

linuxpyro (680927) | more than 2 years ago | (#36002770)

There's a reason for this. In large systems the need for a fast switch from utility to inverter power under full load requires that there be a battery charger constantly charging a battery bank and an inverter or rack of inverters connected to the battery bank to provide power to the load. This isn't very efficient but it works well.

I think this is partly what he was talking about. IE, instead of having a UPS which converts battery power to AC while simultaneously charging the batteries, just have a big DC power supply, float the batteries on it, and use that to power all of the servers and stuff. This does make sense; I have a similar setup with a Mini-ITX motherboard I use as a home mail server and some other things - it has the 12 volt car power supply in it, along with a small 12 volt gel cell battery for backup.

Also battery voltage can vary from about 10 V to 14.4V per battery so I don't think this is tightly regulated enough for computer components. In a large system you want to keep the DC voltage high so your I^2*R power loss is minimalized so DC voltages as high as 108 V are not unheard of.

I think there are commercial systems that operate with DC like this; I know for the telecom 48 VDC is used a lot. This is still a manageable voltage, as high voltage DC is a little more difficult to work with than AC at similar RMS voltages (though I'm sure higher voltages like 108 VDC are used too), but you don't need absolutely huge wire. Also, there are low voltage DC-input ATX power supplies available. I've seen them for 12, 24, and 48 volts. Generally they will produce a regulated output for the PC, so if the battery voltage fluctuates somewhat it's not much of a problem, provided it's within spec. Also, normal AC units usually work by rectifying the incoming line to DC, and then using a step-down converter to get the lower DC voltages. So you could probably run one directly off of 170 VDC (170 volts is around the peak of the AC sine wave).

And of course, if you have a system like this it wouldn't be that hard to throw some photovoltaics in too, which would reduce the load on the main power supply (and thus the draw from the grid).

Re:A Perfect Match (1)

William-Ely (875237) | more than 2 years ago | (#35998684)

Maybe not Elec 101 but 401 (at least in the US). The idea isn't that complicated but there are regulations that make putting a system like that into practice a bit of a challenge (at least in the US). The system must go off-line if the phase drifts, if the line voltage changes by x in y milliseconds, etc...

Re:A Perfect Match (1)

thegarbz (1787294) | more than 2 years ago | (#36005184)

True, but phase drift is incredibly uncommon in inverted power systems due to the fact that the inverter can in practice make whatever frequency it wants and it is completely trivial to lock it with the mains, same goes for all other parameters except for power delivered which is entirely dependent on sunlight.

These piratical problems are actually huge problems with syncing power delivered by rotating equipment (gas turbines, diesel generators) etc which take time to react with line changes, and islanding events are quite common if the mains power and the energy load isn't reasonably steady. Not so much of a problem for Solar PV and any consumer off the shelf mains inverter already has the ability to seamlessly take care of this.

That's the only reason why I said elec101, because you can literally buy the components off the shelf and hook them up with no further engineering problems :-)

Re:A Perfect Match (0)

Anonymous Coward | more than 2 years ago | (#35999662)

I have done the math and solar power just doesn't make sense. For most installations you're looking at 10 to 20 years before recovering the initial investment and by then the solar panels will be running at a fraction of their new capacity (they degrade over time).

At the current prices it just doesn't make economical sense at all. Most likely you will lose money on it over the long run.

Re:A Perfect Match (1)

bberens (965711) | more than 2 years ago | (#35999962)

My power has tiered pricing where the more I use the more it costs per kw*h. I've done the math and for a few thousand bucks I could put together a solar array that offsets that *more expensive* power and could pay for itself in a hand full of years. Generating enough power to cover the lower priced energy is not cost efficient though. YMMV

Re:A Perfect Match (0)

Anonymous Coward | more than 2 years ago | (#36001032)

I have done the math and solar power just doesn't make "sense."

Yes, it makes sense. It's only that it doesn't make the sense you think it should.

It's not about electric consumption, it's about SCR.

"Clean" looks good for the corporation and sun-power looks clean to the public, so let it be.

Re:A Perfect Match (0)

Anonymous Coward | more than 2 years ago | (#36005868)

My panels have 20 (some of them 25) year warranties that promise no less than 80% of rated output for that 20 or 25 year period - they're BP Solar, so I don't expect the manufacturer to disappear in that time frame. I would expect data centres to at least be using a similar amount less per device in 20 years' time. The number of devices will probably go up, though.

Re:A Perfect Match (1)

vivian (156520) | more than 2 years ago | (#36007862)

I have solar installed and it's already making me a 15% return on investment, so I call BS on your calcs. Go redo them.

My panels are guaranteed to still provide 90% capacity or better in 10 years, and 80% capacity or better in 20 years - so yes, over time, they will be running at a fraction of their new capacity - a very large fraction!

Since installation 6 months ago of 3kw of capacity with a 2.8kw inverter, at a cost of $9600, they have already generated 2409 kWh, with a value of between $505 and $1253. If I used all the power, it would have saved me $505, @$0.21/kWh, but if I don't use the power and it's sold onto the grid I get paid $0.52/kWh. In practice, I have actually used about half the power it produces during the day. with the rest getting sold on to the grid, which more than makes enough to cover my night time cost. I used to have an electricity bill of about $400/quarter. On my last bill, I ended up about $120 in credit.

I get paid a higher rate for power I put onto the grid because it of an incentive scheme put in place by both the govt ($0.40 / kwh) and the power company. ($0.12/kwh). It's helping saving the electricity company from having to build additional power stations to meet daytime peak demand.

Seriously, if you have 10k sitting in a bank or poorly performing investment, you should look into what rebates your local,state or federal government provides, find out what the local buy rate is for solar power and check out if it's worth while for your area. It certainly is in mine.

Re:A Perfect Match (1)

Stellian (673475) | more than 2 years ago | (#35997692)

Solar power is a perfect match for data centers. Their power demand is basically constant

Especially if you built it on an asteroid with no clouds and with a side always facing the Sun. Cause you don't need those coal and nuclear plants generating base load, and those huge dams regulating peak load, like on Earth.

Re:A Perfect Match (3, Funny)

daem0n1x (748565) | more than 2 years ago | (#35998358)

This must only be bullshit. Everybody knows solar power is a pipe dream and will never be viable. Data centres should be burning good ole coal and oil, or even tires.

This solar power silliness reminds me of those crazy dudes in the past wasting all taxpayers' money to invent flying machines. Or cures for infections. Or transmitting images over the air in "invisible" waves. All pipe dreams.

Re:A Perfect Match (0)

Anonymous Coward | more than 2 years ago | (#35998604)

Well... actually the flying machines were developed without taxpayer money... taxpayer money was thrown on brother Wright's competitor who was...mildly said.. 'unsuccessful'...

Re:A Perfect Match (1)

daem0n1x (748565) | more than 2 years ago | (#35998700)

Whoooosh is the sound of a flying machine going over your head. This machine is made of a metal called Irony.

Re:A Perfect Match (1)

Shotgun (30919) | more than 2 years ago | (#35999760)

The first one was done without taxes. The real developments that made them useful commercial tools were mostly done in support of....get this....military operations. That was the federal government doing what it was supposed to be doing.

Re:A Perfect Match (0)

Anonymous Coward | more than 2 years ago | (#36000008)

Why do you think data centers are funded with taxpayer money?

Re:A Perfect Match (1)

WelshRarebit (1595637) | more than 2 years ago | (#36004480)

Don't even get me started on the space program. What a waste of taxpayer dollars! In less than 50 years after we wasted billions to put a man on the moon, the much superior PRIVATE sector has already put a person into low earth orbit and promised us a rocket that will be delivered any day now that will be better than the ones we built in the 60's! And people wonder why everyone thinks the government is so inefficient and useless.

Makes sense to me (5, Insightful)

Sycraft-fu (314770) | more than 2 years ago | (#35997208)

While I don't think it would be feasible to run a data center only on solar, it could help with a big thing: cooling. The hotter it is outside, the harder those A/Cs have to work and the more energy they use. Well, conveniently the hotter it is outside the more direct sun the solar panels tend to get so the more power they generate. Kinda of an automatic offset. When the power demand is the most, the panels give you the most.

You'd still need line power to run the data center, particularly at night, but you could help offset your costs in a big way.

Re:Makes sense to me (3, Informative)

TheLink (130905) | more than 2 years ago | (#35997422)

It's actually starting to make more sense.

Previously it had to be subsidized and was more of a way for offsetting your costs to taxpayers, than to the Sun ;).

But from what I see the prices are dropping: http://sunelec.com/index.php?main_page=index&cPath=5 [sunelec.com]

Currently average retail electricity costs are about USD0.09 per kWh (grabbed from DOE). So: ( 1.60 per watt ) / ( 0.09 per kWh) = 2 years.

The sun doesn't shine brightly all the time and there are installation costs etc, so the payback time is about a multiple of that say 8-10 years?

Re:Makes sense to me (2)

Stellian (673475) | more than 2 years ago | (#35997852)

The sun doesn't shine brightly all the time and there are installation costs etc, so the payback time is about a multiple of that say 8-10 years?

I assume they are rated at direct incident light of 1000W/m^2; they have about 13% efficiency, and cost about 200$/m^2.
In United States you have quite a bit of sun [solarpanel...dpower.com] , about 5KW/day/m^2. So you get 0.65KWh per day, on average, for every square meter of installation. You earn about 21$/year/m^2.

It takes 10 years pay it back ignoring the present money value. At more economically realistic 5% interest rate, the payback time is about 20 years, on par with the panel's life time. So much for "free energy". Without ignoring the setup costs and indirect costs from using the power company to regulate your supply when the sun does not shine, the payback time is right about never.

Strictly for the US south-west, solar is borderline profitable when done at the utility level, because they have huge economies of scale. For most of Europe, Canada, Rusia etc. it's a non-starter.

You are assuming... (1)

tanveer1979 (530624) | more than 2 years ago | (#35999140)

That over the next 20 years, there will be no advances in technology leading to better efficiency and lower cost.
Every tech when starts getting adopted is expensive. For example, could anyone afford a computer at home in 1960s?

As technology advances, and costs come down, solar will become more and more viable. So to dismiss a tech just because currently its not economically viable is basically foolhardy.

Re:You are assuming... (1)

bberens (965711) | more than 2 years ago | (#36000028)

I have no doubt that within 20 years solar power will become more efficient. Dropping $30k on a solar system today doesn't mean I get those future improvements for free.

Re:You are assuming... (1)

Stellian (673475) | more than 2 years ago | (#36000124)

Well, if you buy the hardware today, you are locked-out from future advances, and you need to recover that sunken cost. Sure, someday we might harness the energy of flying pigs, and at that point we can have a chat on the economic viability of pigovoltaics. It's in no way foolhardy to pass on investing in something that's a money looser now and might never become viable, especially when we are running pretty close to a fundamental physical limit [cam.ac.uk] of pig buoyancy.

Re:You are assuming... (0)

Anonymous Coward | more than 2 years ago | (#36001462)

It is also assuming power does not get more expensive over time, which it will, outstripping inflation.

I put my solar in 6 months ago and I have already gotten notice of a 12% increase in the top rate. Shortens my payoff time considerably.
It is not a slam dunk, but it makes sense for areas with good sunlight, like the American Southwest, including Silicon Valley.

Re:You are assuming... (0)

Anonymous Coward | more than 2 years ago | (#36001564)

Who cares? The installation that is done NOW will not become more efficient over time - the opposite is true. $1/W solar is less competitive for base load right now than $10/W nuclear. And that's using real numbers.

So what's the magic word that makes the two equal? The magic load is availability. Nuclear is available 24/7. Solar is available sporadically (clouds) with peak at noon.

It also takes 8-10 years to simply generate the energy required by the panel to make that panel, assuming desert location. Energy costs are primary costs of creating a solar panel.

I'm assuming that solar can sell electricity at same price as nuclear - but that is a stretch. If you have enough solar to supply all of electricity, then your spot electricity prices (per supply/demand) will be near NIL during peak generation, during the day. The same energy prices will swing to very high costs at night, when most of solar is offline, maybe $0.25-$0.50/kWh, depending on how we store power. In this scenario, with not enough night time generation, nuclear would pay for itself within 5-10 years simply by idling during the day (ie. lowest power levels) and solar would once again be a loser due to its successful deployment.

So when will solar be very competitive base load? When finally someone starts to deploy solar to geosynchronous orbit and beaming the power down via microwave links. Yes, this can be done safely.

Re:You are assuming... (0)

Anonymous Coward | more than 2 years ago | (#36006068)

It also takes 8-10 years to simply generate the energy required by the panel to make that panel, assuming desert location. Energy costs are primary costs of creating a solar panel.
 
Geez, when will this one get laid to rest? Energy payback is 3 to 5 years.

Re:Makes sense to me (0)

Anonymous Coward | more than 2 years ago | (#36003694)

> At more economically realistic 5% interest rate

Remember, inflation also applies to the electricity costs that the solar panels have saved you. It cancels out. And that's assuming that electricity costs will not exceed general inflation for that entire time period.

Re:Makes sense to me (1)

EETech1 (1179269) | more than 2 years ago | (#36003884)

One thing that you might find yourself doing is balancing your demand with your generation capabilities. When I go camping, I have a panel that will give me 1 amp @ 15VDC when in full sun, and I can go for weeks charging 2 deep-cycle batteries, and running all kinds of electronics, but I have efficient lighting, and do my best not to waste power, and the result is I can run my inflatable boat for a few hours a day for free.

I have a second identical panel, and after years of experimenting with my power distribution and balancing, it finds itself wired directly to the vent fans during normal use, and it does provide a satisfying increase in cooling output when in full sun!

I can't believe the same wouldn't be true for any building. If you were getting a certain amount of power from your installation, you could target other requirements to be able to fall within the capacity of your total solar output, and they can easily have 100% of their power usage offset by solar, even if the Sun only shines 6 hours a day!

Re:Makes sense to me (0)

Anonymous Coward | more than 2 years ago | (#36009254)

The sun doesn't shine brightly all the time and there are installation costs etc, so the payback time is about a multiple of that say 8-10 years?

At more economically realistic 5% interest rate, the payback time is about 20 years,

5% a year from what investment? I'd like to know where you pulled that number from. No investment I am aware of yields an average of 5% a year year over year for 20 years. Please. Let's not throw numbers around we think sound good to support our thesis.

Re:Makes sense to me (0)

Anonymous Coward | more than 2 years ago | (#36000280)

Prices are dropping, but you should know that the module price is only about half of the cost of installing and connecting a PV solar panel. By the time you get any energy out of the panels, it's up to about $3.40 per watt currently. (See: http://www1.eere.energy.gov/solar/sunshot/pdfs/dpw_lushetsky.pdf)

Now, with federal, state and local subsidies this may become economical for the installer -- particularly when the owner can sell electricity at the retail rate instead of at the wholesale rate --, but solar has a ways to go to be competitive on price alone.

Re:Makes sense to me (1)

CrimsonAvenger (580665) | more than 2 years ago | (#36002998)

Previously it had to be subsidized and was more of a way for offsetting your costs to taxpayers, than to the Sun ;).

It still is. Depending on where you live, the tax credits for solar range from fair to impressively large.

Re:Makes sense to me (0)

Anonymous Coward | more than 2 years ago | (#36004212)

Note that for data centers it may make much more sense as they pay a rate based upon the top 3% of their usage in any given month. The lower this peak load the less the electricity for the rest of the month is. Obviously they have the highest cooling needs and highest electricity rates during sunniest days. The rate for commercial electricity is substantially higher than residential retail power prices.

Offset energy usage (5, Interesting)

thegarbz (1787294) | more than 2 years ago | (#35997466)

This hits the nail on the head. Solar PV to offset during the day and grid power at night. I'm sick of Greenies pretending that Solar is the panacea of all things power related, and sick of the short sighted people saying it has no place in power and that's the end of story.

This is where we should be heading. More solar power in plants with a large HVAC requirement. So during the day when it's hot you can offset the cooling energy required, and the result is reducing the grid power which is attainable, rather than replacing base load generation with some magical fairy green power station... which is not!

Re:Offset energy usage (2)

Sycraft-fu (314770) | more than 2 years ago | (#35997558)

Also really helps with distribution which is an issue these days. It is a problem to upgrade the power gird and there are always distribution losses. A good way to mitigate that is more local generation, in particular in response to peak loads. If peak cooling and other loads are handled with local solar, that makes for a much more even load on the grid.

It also compliments many generation technologies well. You find that many kinds of electrical generation are 100% or 0%. There isn't really any "Scale it back as we need less." Also startup and shutdown can be major processes, so you can't do it on a daily basis. Ok well that means waste when demand drops. Again local solar helps there. Keep the demand constant, those stations run constant and life is good.

As you say, not a panacea, but it is an area that it can be real useful in. Put solar on the buildings to help offset peak demand and you address more than one current issue.

Re:Offset energy usage (2)

Stellian (673475) | more than 2 years ago | (#36000354)

Also really helps with distribution which is an issue these days. It is a problem to upgrade the power gird and there are always distribution losses. A good way to mitigate that is more local generation, in particular in response to peak loads. If peak cooling and other loads are handled with local solar, that makes for a much more even load on the grid.

Sorry, but that makes no sense. Solar is in no way a supplier of peak power. It's output spikes widely (10:1) in a cloudy day. So you need to get that power from somewhere else, and have the infrastructure in place to get it.
What solar provides is intermittent power with a low $ value on a liberalised energy market. In order to meet the base-load demands of a data center you need to couple it with expensive hydro or pumped-storage installations, which are constrained to specific geographic locations. So renewables are a disturbance in the grid, and not a way to "even out" the load.

Re:Offset energy usage (2)

Jenming (37265) | more than 2 years ago | (#35999402)

its not that the magical fairy green power stations don't work, its just that fairy mortality rate is still too high and theres no long term plan to store their little radioactive corpses.

Re:Offset energy usage (0)

Anonymous Coward | more than 2 years ago | (#36007146)

Except it's wrong. If the problem is A/C, you'd be more energy efficient coupling ammonia gas absorption refrigerators (A/C) than to solar thermal collectors than grid-tie PV. Double panes easily crank out 200F fluid for hours on winter days.

Furthermore, more HVAC requirements would be better served with geothermal than PV. Geothermal would run all the time, day or night, and reduce the energy load even on hot days without much sun. PVs are only when the sun shines. They're an offset measure to be sure, but much less than what geothermal can contribute.

Sticking PVs on the roof is nice, but it's not so much directly A/C related, more about using roof real estate to generate electricity and reduce the sun's heat on the roof (usually you pop the panels on a metal grid which is slightly off the roof, reflects head, and gives an extra layer of air flow underneath to draw heat away from the panels and underlying actual roof).

Re:Makes sense to me (0)

Anonymous Coward | more than 2 years ago | (#35997492)

While I don't think it would be feasible to run a data center only on solar, it could help with a big thing: cooling. The hotter it is outside, the harder those A/Cs have to work and the more energy they use.

Also just by covering the roof with solar panels they avoid the sun heating up the roof. In Australia this would typically save about 2kW/h of energy during the day due to reduced power usage by the air-conditioning unit most homes have.

Re:Makes sense to me (1)

dbIII (701233) | more than 2 years ago | (#35998238)

Just as you can use solar heat to give you hot water you can also buy industrial sized units that use solar heat to drive the refridgeration cycle. They are serious and large bits of gear with mini cooling towers for condensation but they do exist.

Re:Makes sense to me (1)

Firethorn (177587) | more than 2 years ago | (#36001740)

it could help with a big thing: cooling.

One idea I've seen is to switch to the cheaper solar-thermal panels, w/reflectors. Then you don't use a standard AC unit, you use an adsorption chiller. Electricity usage is restricted to a few pumps that are there more for controllability and efficiency.

To be efficient the water needs to be at least 180F/80C, but that's easily doable with evacuated tube collectors.

Re:Makes sense to me (0)

Anonymous Coward | more than 2 years ago | (#36007106)

"The hotter it is outside, the harder those A/Cs have to work and the more energy they use. Well, conveniently the hotter it is outside the more direct sun the solar panels tend to get so the more power they generate."

Not so much. I don't think it's for A/Cs so much as general electrical use to feedback into the grid to simply offset the electrical load the data center takes up. It's a cost saving measure more than anything with grid tie than a backup option. It's not handling anywhere near the full loads, and they are only investing in roughly half a million in panels per site.

You say solar, but really you are referring to the article and they're referencing PV panels. PVs are good because they produce electricity which can be used for anything electrical.

But if the concern is AC, you'd be better off using a solar heat collector (solar hot water) and coupling that with an absorption refrigerator, or even using a stirling engine setup.

The best energy production would likely be from wind, but that depends on the location. Lots of these are talking big kilowatt numbers, but we just had a food plant recently put up turbines and they were talking megawatts in 15mph winds, which sounds like would work out better for a datacenter than solar. Unfortunately, turbines that size are at least $5million installed each (I forget whether it was $10million for 2 or each), which is a pretty massive up front investment, made worse by all the regulatory bs they'd have to go through to put up the turbines, which they don't have to do with solar.

(Some stupid enviro folks are apparently more worried about bird strikes from slow turbine blades (that they have to report dead birds anyways) over the coal plant stack that'll output crap that birds may fly into and suck in nice friendly fumes and live peaceful, normal lives.)

doesn't have to be the sole source (1, Insightful)

mehu (92260) | more than 2 years ago | (#35997248)

It's not necessary for solar to cover the entire power needs of a data center. It'd be nice if it did, but any power generated is money saved on their electric bill (and less drain on the general grid). And as stated above- they already have lots of batteries to cover (if) any surplus generated, and a fairly constant demand.

Re:doesn't have to be the sole source (2)

Anubis IV (1279820) | more than 2 years ago | (#35997448)

Glad someone else was thinking what I was thinking (and said it better than I would have said it). Mitigating costs by using solar is never a bad idea, especially for operations such as these which do draw so much power.

HVAC first (0)

hterag (39672) | more than 2 years ago | (#35997258)

Well I think its a great step.
But the HVAC needs to be efficent too (maybe more so) . It would make significant improvements to the energy use if the cooling systems were slightly smarter and the build design took it into account, add solar power to that and its a winner.

Re:HVAC first (1)

Sycraft-fu (314770) | more than 2 years ago | (#35997812)

And how would you go about making HVAC more efficient? There's no magic to it, companies keep working on better technologies but it is what it is and there's no magic method to better efficiency that we could use but don't. I would bet data centers invest in efficient HVAC equipment since that is a significant cost savings but there's just only so good you can get. For large facilities about 14 EER is as good as you can get for your equipment. If you want it higher you have to water cool the A/C's condenser coil. That can be done, but of course requires a ready supply of water for the chillers. Over all effective efficiency can be improved with variable capacity units, either having more smaller compressors that can go on and off or using variable digital scroll compressors like AAON uses but that's it.

There are just real limits to A/C efficiency and there is plenty of research going in to trying to make them better, but it is incremental improvements and whatever the best technology is, companies bring it to market.

Re:HVAC first (1)

Stellian (673475) | more than 2 years ago | (#35997900)

And how would you go about making HVAC more efficient?

How about, instead of making electricity at 10-15% efficiency and use it to run a 20-30% efficient refrigerator, switch the whole datacenter to absorption cooling [wikipedia.org] which uses solar heat directly ?

This way, instead of an abysmal solar efficiently of 5% and large capital costs, you get 20% efficiency with some piping and thermal captors.

Re:HVAC first (0)

Anonymous Coward | more than 2 years ago | (#35998898)

Ha! And it uses Ammonia. Another point for your concept :D

Re:HVAC first (1)

hab136 (30884) | more than 2 years ago | (#35999146)

Because absorption coolers don't perform well, especially for heavy loads?

Re:HVAC first (1)

Firethorn (177587) | more than 2 years ago | (#36002030)

They don't perform well? Isn't that just a question of sizing? If they don't work well for heavy loads, why is it that there's lots of them available in huge sizes, but hardly any residential sized units?

Besides, consider the context, even if adsorption chillers aren't as efficient as HVAC versions.
1. Solar heat panels are cheaper than solar electric panels.
2. Solar heat panels are more efficient than solar electric (30-90%, vs 13%)

Basically, the cheaper panels helps to offset any increased costs on part of the adsorption system, while the higher efficiency helps offset any losses in efficiency.

Re:HVAC first (1)

jbengt (874751) | more than 2 years ago | (#36002918)

Cheap solar thermal panels do not run at high enough temperatures to make absorption refrigeration efficient.

Re:HVAC first (1)

Firethorn (177587) | more than 2 years ago | (#36004146)

cheaper != cheap.

I never said that they'd be able to use bargain basement thermal panels.

Still, Evergreen Es-A-210-Fa3 [solarhome.org]
210 watt, 13% efficiency, 65"x37.5" = 2,438 square inches of collector(1.57m2). $587 each bought in a pallet of 28.

Cost by area: $374 m2
Power by area: 134 w/m2
Cost per watt: $2.79

A "ThermoPower-VDF30 [sunmaxxsolar.com] should be around $1,244.
It's aperture is 2.67 m2. 94% absorbtion, 7% emission per the datasheet [siliconsolar.com] . 'Stagnation Temperature" > 428F

Cost by area: $466 m2 (okay, it's not cheaper per m2)
Power by area: 634 w/m2 (at 1000 w/m2) (almost 5 times the power though)
Cost per watt: $0.74

Conclusion: At 27% of the price, you'd have to be looking at a pretty hefty penalty for using an adsorption chiller for it to make sense to use electrical HVAC with solar electric panels. Also, in either case I'd consider utilizing additional reflectors to put more power to the relatively expensive collector.

Re:HVAC first (1)

BranMan (29917) | more than 2 years ago | (#36003418)

Plus, the adsorption chillers are, comparatively, solid state. Little to zero cost to run or maintain, so all capital costs. Sounds like a no brainer - to at least handle the 'base load' of cooling (so to speak), and run the HVACs as needed only.

Re:HVAC first (1)

dbIII (701233) | more than 2 years ago | (#35998216)

There is solar airconditioning at industrial scales. Refridgerated AC is a heat pump after all and solar heat is about as good as any other once you get away from the small scale domestic units.

Not yet fully powered (3, Insightful)

c0lo (1497653) | more than 2 years ago | (#35997280)

TFA cites 4 examples, none of which reached the level of self-sufficiency. So, while a step in the good direction, the data centers haven't yet reached "to generate the levels of energy required by these facilities" (as TFS suggest).

Anyway, one can only hope the trend will continue, even if only for two very selfish reasons:
a. the more mainstream the PV are, the lower the price on all the market (10 years to ROI for a decent PV home installation is still too expensive to my taste).
b. the more pressure on energy consumption to run a data center, the higher chances computer (part) manufacturers to research techs with lower energy requirements.

I reckon both of them would be good (medium/long term) for my pocket as well.

Re:Not yet fully powered (3, Insightful)

DrVomact (726065) | more than 2 years ago | (#35997866)

TFA cites 4 examples, none of which reached the level of self-sufficiency. So, while a step in the good direction, the data centers haven't yet reached "to generate the levels of energy required by these facilities" (as TFS suggest).

Anyway, one can only hope the trend will continue, even if only for two very selfish reasons: a. the more mainstream the PV are, the lower the price on all the market (10 years to ROI for a decent PV home installation is still too expensive to my taste). b. the more pressure on energy consumption to run a data center, the higher chances computer (part) manufacturers to research techs with lower energy requirements.

I reckon both of them would be good (medium/long term) for my pocket as well.

But why do you want to buy photovoltaic (PV) panels in the first place? Do you think it's just intrinsically good for some reason? Suppose we cover every available architectural surface in our cities and towns with solar panels. Does this have any non-obvious downsides?

  1. You talk about amortizing the cost of the solar panels to you. But what about the environmental impact of manufacturing the panels? Does it create pollutants? What are the consequences of exploiting the raw materials to make the panels? Does mining them cause pollution? What are the costs of rectifying these effects?
  2. Presumably, it takes energy to mine the raw materials and to make the panels. Where does this energy come from? Again, this is not usually considered in calculating the amortization costs of the panels. If oil was burned to do any of this, aren't you adding to your "carbon footprint" by buying so many panels?
  3. These panels have a finite lifespan (I believe it's about a decade). What is the environmental impact of disposing of them? Can the components be recycled? What are the energy requirements of doing this? And again, how does it add to your "carbon footprint" to expend the energy to handle the dead panels?

People are happier if they don't think about this, so I don't suppose many will. They will just buy PV panels and feel all warm about themselves...or make governments and corporations do it, to have more of those warm fuzzy feelings floating around.

Not that it matters, but I just bought a PV panel because I'm going to be spending a few months in an isolated area, and need a little electricity to power my personal gadgets. But then the only alternative would be a petro-powered generator, and I'm not putting up with the noise or smell. I might even stick a few panels on my house; not because it's intrinsically good, but as a backup for those times when the grid fails.

Re:Not yet fully powered (1)

c0lo (1497653) | more than 2 years ago | (#35998118)

Now, all the above/below are good questions indeed! I'm serous when saying it. Even if you won't reply with some extra information (I'll appreciate if you will), I'll look for it myself.
Without invalidating the legitimacy of the questions, I'll try to give you another perspective on possible reasons for "going solar", please see if they don't make a valid PoV.

But why do you want to buy photovoltaic (PV) panels in the first place? Do you think it's just intrinsically good for some reason?

Yes, the very intrinsic and personal (egotistical) reason: potentially independence from the power grid for me as a person - one less thing I need to depend on a corporation. Without the smell, the noise and the price of fuel and whatnot associated with burning fossil fuel.

Suppose we cover every available architectural surface in our cities and towns with solar panels. Does this have any non-obvious downsides?

You talk about amortizing the cost of the solar panels to you. But what about the environmental impact of manufacturing the panels? Does it create pollutants? What are the consequences of exploiting the raw materials to make the panels? Does mining them cause pollution? What are the costs of rectifying these effects?

(did I mention some egotistical motives? Yes, I did). I really don't know. Do you? Can you share some estimation with us?

Presumably, it takes energy to mine the raw materials and to make the panels. Where does this energy come from? Again, this is not usually considered in calculating the amortization costs of the panels. If oil was burned to do any of this, aren't you adding to your "carbon footprint" by buying so many panels?

(did I mention some egotistical motives? Yes, I did). Do I add to the carbon footprint? I don't know, can you please share with us any estimation between "carbon saved"/"carbon expended" for the current level of technology?

These panels have a finite lifespan (I believe it's about a decade)

They use to advertise them for 25-30 years.

What is the environmental impact of disposing of them? Can the components be recycled?

Mainly silicon/silicon dioxide. Inert. Even if not recycled, not more harmful than non-recycled glass bottles or broken windows.

What are the energy requirements of doing this? And again, how does it add to your "carbon footprint" to expend the energy to handle the dead panels?

(did I mention some egotistical motives? Yes, I did).

People are happier if they don't think about this, so I don't suppose many will. They will just buy PV panels and feel all warm about themselves...or make governments and corporations do it, to have more of those warm fuzzy feelings floating around.

Not that it matters, but I just bought a PV panel because I'm going to be spending a few months in an isolated area, and need a little electricity to power my personal gadgets.

Now, suppose that you would need more than a little. Are you quite sure the PV are not a solution? (because I see questions, but no attempt for answers, even partial).

But then the only alternative would be a petro-powered generator, and I'm not putting up with the noise or smell. I might even stick a few panels on my house; not because it's intrinsically good, but as a backup for those times when the grid fails.

Re:Not yet fully powered (2)

Stellian (673475) | more than 2 years ago | (#35998406)

(did I mention some egotistical motives? Yes, I did)

Even in a purely purely egotistical approach, it should be clear that the PV cell's price is heavily subsided by the cheaply available fossil fuel, which is used intensively in mining and manufacturing. There's no way to "go solar" without a large electric storage, which will degrade much more quickly than 25 years. A technology which is borderline profitable now will become prohibitively expensive assuming a high oil price.

Re:Not yet fully powered (1)

c0lo (1497653) | more than 2 years ago | (#35998680)

(did I mention some egotistical motives? Yes, I did)

Even in a purely purely egotistical approach, it should be clear that the PV cell's price is heavily subsided by the cheaply available fossil fuel, which is used intensively in mining and manufacturing. There's no way to "go solar" without a large electric storage, which will degrade much more quickly than 25 years. A technology which is borderline profitable now will become prohibitively expensive assuming a high oil price.

I'm mildly objecting to the "subsidized" term (assuming that's what you actually wanted to say): it is not that PV cells are favored more than, say, any smart phone or, actually, anything else that uses energy/minerals in the fabrication process (including cement - I'll come to it later). Otherwise, you are right: the PV prices will be affected by the current prices of energy, hard to predict if the PV prices will go down (entering "mainstream" economics) or up (because the price of energy going up).

Now, about cement: you'll find it in most of the buildings (think: concrete). Some bad mouths say [wikipedia.org] that, energetically and CO2 footprint, cement is really bad (900 kg CO2 per every 1000 kg cement. 360 kg CO2 is the footprint of the burnt fuel). I don't know yet, but... in the context of covering a building with PV panels... I somehow feel that the concrete in the building has had a worse CO2/energy footprint than the PV-es.

Re:Not yet fully powered (1)

swb (14022) | more than 2 years ago | (#36000644)

I ask those same questions about hybrid cars. The electric motors, batteries and more extensive electronics for regulating and controlling all of it takes real energy to mine and manufacture; rare earths likely used in the motors are not just intensive to mine but produce a ton of pollution to process.

I've even read that cars like Priuses with small tires consume more tires over their lifespan, further increasing their pollution in the vehicle's lifecycle.

Re:Not yet fully powered (1)

timeOday (582209) | more than 2 years ago | (#36000100)

TFA cites 4 examples, none of which reached the level of self-sufficiency

Data centers would be among the last places to ever be 100% local solar, for several reasons:

  • They use a massive amount of electricity in a small area
  • They are 24 hour operations
  • They require high availability (i.e., even the regular electric is not reliable enough without backups)

None of this is really a knock on solar, data centers just happen to be one of the more demanding consumers of electricity out there. But blunting their impact with solar seems like a good idea, since no matter when the sun is shining, or how much, there will be a need for it right then and there.

new territory discovered; americannex (-1)

Anonymous Coward | more than 2 years ago | (#35997444)

no longer an abstract unproven nounjective, this is now US. some strings still have yo be pulled, but this mini oneification provides enriching momentdumb for the glorious glowering felt by the profitsized chosen .5 billion remaining population with lots of room to grow day, to be celebrated in 2025. as it is written. on to mebotuh.

disarm. sun censoring has ended? the wars are ended? the hateful punishing self-worshiping chosen ones' delusional neogods are ending? better days ahead for sure then.

life & death remain fear control based notions (-1)

Anonymous Coward | more than 2 years ago | (#35997626)

all we have for evidence is babys & carcasses. this muck in between, must be the 'life' part? as far as we cannot see.... so far... is yet to be conclusive, because, it's just not yet.

the alleged so-called whore of babylon has escaped, again, temporarily. the identifying papers she was carrying, have been appropriately hidden, for our protection, from ourselves, & our self-appointed rulers & administrators of the deities' unending holycost.

Motivation? (0)

Anonymous Coward | more than 2 years ago | (#35998552)

It's less about the power and more for the tax breaks, obviously.

Avoided heat (0)

grizdog (1224414) | more than 2 years ago | (#35998676)

Does anyone have any idea how much energy these panels will be saving simply by using the sunlight for something other than heating the building? I realize you could accomplish much the same thing with a simple awning, but it seems like it should still be part of the calculation.

Re:Avoided heat (0)

Anonymous Coward | more than 2 years ago | (#35998808)

My guess is that the effect is actually negative. Instead of white paint which is relatively reflective, you get dark panels which absorb a lot more heat, but only use 10-20% to produce electricity.

Re:Avoided heat (1)

Shotgun (30919) | more than 2 years ago | (#36000066)

Yes, but unless the panels are attached directly to the building, there will be a cooling air gap to keep the heat away from the building. Besides, most roofs are already black.

Re:Avoided heat (1)

jbengt (874751) | more than 2 years ago | (#36005202)

Most new (commercial) roofs are white, reflective (silvery), or at least light colored, and are often required to be so by energy codes.

Re:Avoided heat (0)

Anonymous Coward | more than 2 years ago | (#35998932)

Yes. The amount of energy saved will be precisely zero. It takes approximately 35MWh of electricity to produce 1kW of PV capacity according to BP Solar. So, 1kW of PV capacity would need 35,000 hours of full sun just to replace the electricity that was used to create it.

We just installed 55kW of PV capacity at our factory facility as a gesture of green intentions despite our consulting firm finding that we'd neither pay for the cost of installation nor replace the energy used to produce and install the array.

Re:Avoided heat (1)

angel'o'sphere (80593) | more than 2 years ago | (#36000524)

It takes approximately 35MWh of electricity to produce 1kW of PV capacity according to BP Solar.

That is wrong, likely it is a typo.
Regards
angel'o'sphere

If you are able... (0)

Bizzeh (851225) | more than 2 years ago | (#35999266)

if you are able to, and able to afford solar power installation, you really should. the amount of energy panels produce to the cost of the panels per square foot means, to produce all your electricity for a home or business with solar, costs about 7 - 10 years of your energy bills, and most panels now are guaranteed to last a minimum of 25 years. not only will they eventually save you a lot of money (as energy costs are only going to go up), they can allow you to make money if you get a "feed-in-tariff" that allows you to sell your excess production back to the grid

Re:If you are able... (2)

bberens (965711) | more than 2 years ago | (#36000138)

I support the solar power *movement* but this simply isn't true. It costs about $30k for me to replace my current electricity usage. At an average power bill of $150/mo it'll take 200 months or 16.7 years to pay off. That assumes I have $30k lying around I don't need. Now if energy costs triple in 5 years I'll be quite sad that I didn't get that solar system, but even putting that money in a pitiful money market account at the local credit union will offer better returns than the PV system today. And the net carbon usage to mine and manufacture the solar panels still isn't that good.

Simple economics. (1)

Anonymous Coward | more than 2 years ago | (#35999950)

Here's the skinny -

PV Costs about $5 per watt, installed (and that's cheap. It's usually much more). Never mind the cost of the silicon technology, the majority of that cost is in brackets, adhesives, other hardware, wires, labor... Costs which are fully mature and not going to go down. So, assume an average upper middle-class house in south Texas that uses roughly 100 kWh per day (Central A/C in a large-ish house is a bitch!) and forget about batteries. So a 10 kW system is going to cost us $50,000 (10,000 watts * $5) and generate 60 kWh per day, during the daytime only (6 hours of good direct sun). We still need grid power to get to our 100 kWh usage.

Similarly, that Grid power only costs $0.12/kWh, so the same power from the grid only costs us $7.2 per day vs. the $50,000 solar array. (And trust me, when it's 105 degrees in the summer time, for months at a time, that $7.20 feels damn cheap.)

Going further, $216.0/month for grid power, vs. a $330/month payment on a 20 year loan @ 5% interest.
Or, better yet, invest your $50,000 that you already have in an index fund, get an average 7% return and EARN $390 per month over the next 20 years. Now your grid power is free and you make an extra $174/month, and have zero maintenance worries (dust, corrosion, etc.) or insurance costs (hail, baseballs, etc.)

And that's only in the summer time. My winter electricity usage is about half that, which makes the solar picture even bleaker.

People who value their money more than their conscience will never buy solar, until the cost of grid power essentially doubles. And to be truly competitive, the cost of grid power needs to triple. But what would that do to our economy when everything you buy has power as one of its major embedded costs?

Re:Simple economics. (1)

vivian (156520) | more than 2 years ago | (#36007984)

100kwh/day? that's a huge amount of power to be using! Even in Dallas, the city with the highest average, the average residential power usage is 44 kWh/day per customer. Nationally in the US, it's lower, about 30kWh per day.

At that rate of power usage, and with the low cost of subsidized electricity where you live, Solar will not be a viable option for you for quite some time, if ever. $0.12/KWh is about half what it costs here in Australia - and we sell a hell of a lot of coal, so I can only assume that there's some big subsidies there which don't exist here in Aus.

You could definitely look into better insulation, strategically placed shade (either from trees or awnings etc) to reduce direct sun on your house, and possibly renovations that would allow for better natural cooling to cut down that monster bill though.

Re:Simple economics. (1)

An Onerous Coward (222037) | more than 2 years ago | (#36010170)

Honestly, if you have $50K to invest in lowering your carbon footprint, there are more effective ways to do it. Move closer to work. Buy a bus pass, a nice bike, and some bad weather gear. Solar hot water heater. Energy efficient appliances and lighting.

I like solar, I really do. But too many people talk about it like it's the be-all and end-all of green living. Energy efficiency is a much better return on investment right now.

Once you've made all those investments, you'll need a much smaller solar array anyhow.

It's just a PR stunt? (4, Insightful)

hawguy (1600213) | more than 2 years ago | (#36000264)

Does anyone see this as anything other that a PR stunt? Facebook's datacenter uses 30MW of electricity -- a 100KW solar panel array will produce 0.1% of their power - not even a drop in the bucket. (note that it's not 0.3% since the solar panels don't provide power all day).

If they were really interested in reducing their carbon footprint with solar, they'd be investing in one of the large-scale power plants being built in the desert where they can buy more KW per dollar. it doesn't matter whether they reduce carbon in Arizona or in Oregon, it's all the same to the environment.

And if they were *really* interested in reducing their carbon footprint, they'd use a small nuclear reactor [hyperionpo...ration.com] to generate 100% of their power on-site. Which would make a *real* difference in their carbon footprint rather than a meaningless symbolic gesture.

Re:It's just a PR stunt? (0)

Anonymous Coward | more than 2 years ago | (#36001730)

Well, nuclear is not competitive and it is much more of a "hustle" than solar. Solar brings PR, nuclear brings irrational fear. Furthermore, nuclear tends to be competitive only at a very large size. Since there is a very large grid it can connect to, building smaller than about 1GWe does not make sense.

Otherwise you are spot on. This is just a PR move.

PS. The link seems like a niche market for isolated installations.

Re:It's just a PR stunt? (1)

hawguy (1600213) | more than 2 years ago | (#36005606)

If Hyperion (among the half dozen or so other companies that want to sell small nukes ) can fulfill their promises, a small nuke can make sense. $50M for a 25MW reactor that lasts 8 years means power costs 3 cents/KWh. Of course, none of the makers have NRC certification so who knows how much the final design will cost, especially when factoring in liability insurance and dismantling costs.

I don't know what commercial rates are for larger power consumers, but 3 cents seems pretty competitive.

The Hyperior reactor at the link I gave is definitely a niche market, you probably won't see one on every street corner, but it's not just for isolated installations since they say that hospitals, universities, etc can benefit.

Re:It's just a PR stunt? (1)

Rutulian (171771) | more than 2 years ago | (#36019888)

Well, this is an interesting idea, but the major cost being left out of this calculation is the operating cost. No nuclear reactor will be licensed to operate in the US without a full staff complement. At a minimum, this usually entails two full-time licensed nuclear reactor operators, security, and auditing and regular safety review.
Don't be fooled. This is a power plant, even if it is a small one. It's not going to be economical for a random business. The website says it would work for things like large government and hospital complexes. In these cases it might be conceivable to hire staff to run an in-house power generation facility, but I doubt it would work out for an office building downtown.

I have a bridge for sale too (0)

Anonymous Coward | more than 2 years ago | (#36000870)

A solar panels to day will make about 180 to 250 watts in good sunlight near noon and is twice as large as 1 RU rack server. We put 42 servers in a rack. Now if you take into account the extra space between the racks and apply that for A/C then you still can cover about 1/80 of the needs of a data centre with modern solar near noon.

works great here (0)

Anonymous Coward | more than 2 years ago | (#36001642)

My Internet outpost "in the boonies" is 100% solar-powered. Cheap panels from sunelec.com, commodity motherboard with DC-DC power supply from mini-box.com, golf cart batteries (shorter life, but cheap) from a local supplier. A bucking DC-DC converter makes a small amount of 48VDC for the telco hardware.

I built the whole thing for less than the install fees demanded by the local power monopoly.

A for effort (0)

Anonymous Coward | more than 2 years ago | (#36002824)

They get an A for effort: a solar panel can provide enough power to run a coffee maker, and perhaps a bit of cooling. Some might think I'm being cynical, but I'm not. The truth is that the energy from the sun (at the equator) on a cloudless day at noon is 8 watts per square meter. Solar panels are less than 20% efficient, but for the math give them a full 20%. So 1 square meter of panels produces 1.6 watts. Lets say that the data center has 5 rows of panels, 2 meters by 60 meters (6 feet by 197 feet). So each row is 120 square meters, and the entire array is 600 square meters. It can produce 960 watts of power. A small coffee maker is only 600 watts, a bigger model is 900 watts, and in an office, you want the bigger one. Of course, it could run a single PC (my machine has an 800 watt power supply). I don't pull 800 watts from it all the time, usually its less than that, but for the cost of the panels, you could purchase power for the datacenter for a year. Oh, and as for transportation, the area of the panels is roughly equivalent to the sides of 3 city busses end to end by the height of each bus. And an area that size produces 1 1/4 horsepower, kinda like an underpowered moped.

Re:A for effort (0)

Anonymous Coward | more than 2 years ago | (#36005968)

8 watts/sq.m ? Where did you get that from? The level of insolation at the equator is very close to 1000 watts/sq.m.

Check for New Comments
Slashdot Account

Need an Account?

Forgot your password?

Don't worry, we never post anything without your permission.

Submission Text Formatting Tips

We support a small subset of HTML, namely these tags:

  • b
  • i
  • p
  • br
  • a
  • ol
  • ul
  • li
  • dl
  • dt
  • dd
  • em
  • strong
  • tt
  • blockquote
  • div
  • quote
  • ecode

"ecode" can be used for code snippets, for example:

<ecode>    while(1) { do_something(); } </ecode>
Sign up for Slashdot Newsletters
Create a Slashdot Account

Loading...