Author Topic: Exergy, another Bullshit "save the world" project  (Read 22387 times)

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Offline ltorsini

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Re: Exergy, another Bullshit "save the world" project
« Reply #50 on: October 14, 2015, 05:14:55 am »
Hi,

As you've discovered, the audience here is generally technically astute, but also deeply unforgiving when it comes to even a whiff of marketing over substance. On a bad day I'm as guilty of this as anyone.

Your idea to use the waste heat from a computer for something useful, in preference to simply generating heat with a resistor, is fine. I don't think anyone's questioning that principle. For an audience with a strictly electronics (but not thermodynamics) background, it might do you no harm to explain why running a heat source at a higher temperature can be a good thing when it comes to making use of that heat elsewhere.

Given that you obviously understand this already, you shot yourself in the foot when you mentioned Solar Roadways in your campaign. That project was the poster child for marketing over feasibility. Guilt by association, I'm afraid.

If you want to win over a technical audience, you need to explain, quantitatively, what your product actually does and how it might be useful. A simple explanation about its power consumption, MIPS per Watt, operating temperature, and the method for ultimately extracting the heat produced and making use of it, would go a long way. Above all, you just need to demonstrate that you have a strong understanding of the physics, and that you're not trying to do something for which the numbers simply don't add up.

A purposely inefficient computer would be a bad idea... no better than a laptop plus a bar heater. One which is just as good in terms of MIPS per Watt as any other server, but capable of running at a high temperature and providing a means to make good use of the heat that would otherwise be wasted, is potentially quite a good one.

I still think you should use a standard desktop CPU and make coffee with it, though!

The idea isn't actually to reuse waste heat from a computer.  The idea it to generate primary heat from computation, there is a pretty significant difference.  Waste heat from computers is typically too low in temperature to be able to do anything too terribly useful.  Increasing the maximum operating temperature of computing is the interesting proposition. Even if the compute used to make heat were slow and hot it would still be delivering a useful benefit beyond just heat.

At a higher level, far more of the energy we pull out of the ground to run our economy today is used to make heat than it is to make electricity.  With climate change concerns and the rapid shift to distributed, renewable generation sources - wind and solar specifically - there will be a shift in the way we make heat.  Combining computation and high temperature heat generation produces at least two primary benefits from the same energy source and far too many ancillary benefits to list.

MIPs per usable BTUh is likely a better measure of the effect we are looking for and the focus of the next stage of development. MIPs per Watt is a pretty irrelevant design feature at this stage, we have a few more important hurdles than optimizing MIPs per Watt. I'm sure you can understand that I'm not terribly interested in telling a forum too many specific details about how we are going to generate, capture and store the heat. 

Hopefully you have enough information at this point to understand that Project Exergy is not 'another Bullshit "save the world" project' at this point and that the approach is viable and well within the realm of technical feasibility?  If not I'm certainly willing to answer some more questions if you think this is more 'marketing vs substance'.
 

Offline ltorsini

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Re: Exergy, another Bullshit "save the world" project
« Reply #51 on: October 14, 2015, 05:30:58 am »
As die temperature increases, its common for CPUs to become increasingly less efficient, requiring more power to do the same operations. Do the benefits of this system outweigh the extra power consumption?



The increase in this example, for instance, is larger than the power consumed by a more powerful cooler so one could actually be wasting more energy by using less cooling power. Which isn't directly related to this particular use, but you're still drawing more power than you would otherwise, which is not "free".

The economics are the opportunity.  With today's chips, the system may not produce the optimal MIPs/usable BTUh.  If there is enough of economic incentive, considering 2% of US electricity used for Data Centers vs ~20 used for heat alone in buildings, we're pretty sure there will be significant interest in optimizing chips to run hot.  Fraunhofer estimates the cost to optimize chips to run hot and fast are by no means insurmountable.
 

Offline daqq

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Re: Exergy, another Bullshit "save the world" project
« Reply #52 on: October 15, 2015, 06:46:05 pm »
It seems a bit unrealistic to expect industry to change that much for the sake of this. From what I've understood from your comments it can work very well, provided that the industry moves to a different type of process (tungsten for interconnects) for semiconductors that will be used exclusively* for a new heat-to-MIPS computer class. This would also require a lot of other processes and techs that are meant exclusively for that class of computers - high temperature PCBs, high temperature misc support components...

I'm quite sure it's possible, but basically this would only get you a relatively small increase** in computation power during winter in certain areas of the world.

* The reasoning behind the exclusively part is that pretty much everyone in the market wants more power efficient devices rather than purposefully wasteful devices.
** Until the next generation of computational devices set the bar higher by conventional, energy efficient means.
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Offline ltorsini

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Re: Exergy, another Bullshit "save the world" project
« Reply #53 on: October 16, 2015, 02:34:25 am »
It seems a bit unrealistic to expect industry to change that much for the sake of this. From what I've understood from your comments it can work very well, provided that the industry moves to a different type of process (tungsten for interconnects) for semiconductors that will be used exclusively* for a new heat-to-MIPS computer class. This would also require a lot of other processes and techs that are meant exclusively for that class of computers - high temperature PCBs, high temperature misc support components...

I'm quite sure it's possible, but basically this would only get you a relatively small increase** in computation power during winter in certain areas of the world.

* The reasoning behind the exclusively part is that pretty much everyone in the market wants more power efficient devices rather than purposefully wasteful devices.
** Until the next generation of computational devices set the bar higher by conventional, energy efficient means.

Thanks for the input - we'll stick with the recommendations from the DoE/ARPA-e and continue pursuing the project.  It was a bit unrealistic for Henry Ford to make a car that everyone could afford... he still did.
 

Offline Nerull

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Re: Exergy, another Bullshit "save the world" project
« Reply #54 on: October 16, 2015, 04:10:17 am »
I hope you don't imagine that appeals to the past inspires any sort of confidence, since this is generally the first resort of the nutcase. "THEY LAUGHED AT EINSTEIN!!121231"
 

Offline ltorsini

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Re: Exergy, another Bullshit "save the world" project
« Reply #55 on: October 16, 2015, 06:01:41 am »
Thanks Nerull,

We're really not looking for approval, just hoping to pass along some real information about the project.

Any more technical questions, Guys?
 

Offline jwm_

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Re: Exergy, another Bullshit "save the world" project
« Reply #56 on: October 16, 2015, 06:27:03 am »
An issue is that directly converting electricity to heat is not the best way to use electricity to heat a house.

You can be 100% efficient with a simple heater (or CPU), but with a heat pump, you can actually be several times more efficient. The idea is you use the electricity to pump heat from the outside in, so you heat up your house not only by the waste heat of the pump, but by the actual heat that was pumped into the house. getting maybe 200% efficiency.

It's like installing your air conditioner backwards. Heat from electricity + heat plus pumping is more than you can get just by running a CPU or a space heater etc.

Offline edavid

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Re: Exergy, another Bullshit "save the world" project
« Reply #57 on: October 16, 2015, 06:43:58 am »
Thanks Nerull,

We're really not looking for approval, just hoping to pass along some real information about the project.

And we all know that smugness is the best way to save the world :)

It will be nice to get that real information though.
 

Offline timb

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Re: Exergy, another Bullshit "save the world" project
« Reply #58 on: October 16, 2015, 06:50:48 am »
So, instead of putting these in houses, why not target them towards data centers? Use the heat to create high temperature steam, drive a turbine generator and use that to power the systems. Obviously you can't self-power the system this way, unless you've also broken some thermodynamic laws, but it would go a long way towards reducing the power consumption of the data center. Plus you wouldn't need all the cooling capacity.


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Offline AndyC_772

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Re: Exergy, another Bullshit "save the world" project
« Reply #59 on: October 16, 2015, 06:58:39 am »
A domestic hot water cylinder sits at around 70 deg C.

Why all the work on high temperature semiconductors, when you could build a drop-in replacement for an electric immersion heater out of a CPU with a small pump and a heat exchanger?

What's the compelling application for the higher temperature?
 

Offline ltorsini

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Re: Exergy, another Bullshit "save the world" project
« Reply #60 on: October 16, 2015, 08:01:49 am »
An issue is that directly converting electricity to heat is not the best way to use electricity to heat a house.

You can be 100% efficient with a simple heater (or CPU), but with a heat pump, you can actually be several times more efficient. The idea is you use the electricity to pump heat from the outside in, so you heat up your house not only by the waste heat of the pump, but by the actual heat that was pumped into the house. getting maybe 200% efficiency.

It's like installing your air conditioner backwards. Heat from electricity + heat plus pumping is more than you can get just by running a CPU or a space heater etc.

Salient point.  If we are just looking at the most efficient way to heat a house then solar or geo thermal with storage is the hands down winner and heat pumps (space heat and DHW) are a the most efficient uses of electricity to heat.  But looking at it from a macro level, 2-3% of US (slightly less global) electricity is consumed in datacenters, 30-60% of that is used to eliminate waste heat by pumping it top the atmosphere.  The growth of data collection and number of data centers is growing rapidly and the growth has no end end in sight so, by some accounts, this is a problem that is compounding. http://www.sciencedaily.com/releases/2013/05/130522085217.htm

Other side of the coin, 30% of the total energy we consume is used to heat buildings.  Combining the two eliminates the wasted energy pumping heat to the atmosphere and displaces energy we were using to do just one thing - compute or heat.  So the macro economic potential is very large.
 

Offline ltorsini

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Re: Exergy, another Bullshit "save the world" project
« Reply #61 on: October 16, 2015, 08:04:21 am »
Thanks Nerull,

We're really not looking for approval, just hoping to pass along some real information about the project.

And we all know that smugness is the best way to save the world :)

It will be nice to get that real information though.

I count 3 pages of smugness before I entered the conversation.  If you have a need for information then feel free to ask a question?
 

Offline ltorsini

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Re: Exergy, another Bullshit "save the world" project
« Reply #62 on: October 16, 2015, 08:07:19 am »
So, instead of putting these in houses, why not target them towards data centers? Use the heat to create high temperature steam, drive a turbine generator and use that to power the systems. Obviously you can't self-power the system this way, unless you've also broken some thermodynamic laws, but it would go a long way towards reducing the power consumption of the data center. Plus you wouldn't need all the cooling capacity.


Sent from my Tablet

The designs are modular so they could be used in a datacenter but, you are right, converting heat back to electricity would be a loss vs using the heat for heat.  We have looked at Organic Rankine Cycle generation but the numbers favor creating heat where we need it.
 

Offline ltorsini

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Re: Exergy, another Bullshit "save the world" project
« Reply #63 on: October 16, 2015, 08:12:04 am »
A domestic hot water cylinder sits at around 70 deg C.

Why all the work on high temperature semiconductors, when you could build a drop-in replacement for an electric immersion heater out of a CPU with a small pump and a heat exchanger?

What's the compelling application for the higher temperature?

The need for heat is pretty seasonal so increasing temperature and running absorptive chillers/refrigeration  or regenerating desiccant for evaporative space cooling will extend the system's benefits through the summer months and increase the benefits.  It may not make the economic break even, that's why we are doing the research.  It is an absolute slam dunk for DHW, much cheaper system.

And I think it would be pretty cool to cook my thanksgiving turkey with compute one day...   8)
« Last Edit: October 16, 2015, 08:25:56 am by ltorsini »
 

Offline JacquesBBB

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Re: Exergy, another Bullshit "save the world" project
« Reply #64 on: October 16, 2015, 09:02:41 pm »
But looking at it from a macro level, 2-3% of US (slightly less global) electricity is consumed in datacenters, 30-60% of that is used to eliminate waste heat by pumping it top the atmosphere.  The growth of data collection and number of data centers is growing rapidly and the growth has no end end in sight so, by some accounts, this is a problem that is compounding.

You keep saying that data centers use 30-60% of power to eliminate wasted heat, unless they go to the Artic where data transmission become a problem.

But although these figures can be reached by old generation data centers, there are some alternative ways of reducing
power overhead that is used in modern data centers.
For example, the large Facebook data center of Prineville has a PUE of only 1.07  (only 7% overhead)
https://www.facebook.com/notes/facebook-engineering/designing-a-very-efficient-data-center/10150148003778920

In the computer center that I run, with more than 2000 Xeon cores, we have a PUE of less than 1.04 (and this is at latitude 45 deg,  not in the Artic)
right where we work.  The cooling is made, as in the Facebook data center with  direct air cooling and water evaporation for
the  warmest days.


Quote
Fraunhofer estimates the cost to optimize chips to run hot and fast are by no means insurmountable.

You keep mentioning your  Fraunhofer contract  as a validation for your project, but it is very unclear what exactly is your Fraunhofer contract.

It is well established that  there is a current research for  increasing the  running temperature of the computer chips. This is a way to reduce the cost
of cooling the computer centers by letting them run at higher temperature. This has nothing to do with your present project, which is running on purpose the
cpu to high temperatures to heat habitations.

« Last Edit: October 17, 2015, 04:53:16 am by JacquesBBB »
 

Offline dfmischler

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Re: Exergy, another Bullshit "save the world" project
« Reply #65 on: October 17, 2015, 12:30:41 am »
What about the problem of heat requirements fluctuating over short periods of time?  For example, my family's greenhouses need almost no additional heat during even the coldest winter days due to incoming solar radiation, but may need massive heat (as much as 1MW) on a cold winter night  Could this match any kind of computation demand?

Even my own well-insulated house built in 1998 has a heat loss in excess of 15KW at the lowest outdoor temperatures.  Do you plan to stage computation up and down to match heat requirements?
« Last Edit: October 17, 2015, 07:38:53 am by dfmischler »
 

Offline ltorsini

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Re: Exergy, another Bullshit "save the world" project
« Reply #66 on: October 18, 2015, 06:56:49 am »
But looking at it from a macro level, 2-3% of US (slightly less global) electricity is consumed in datacenters, 30-60% of that is used to eliminate waste heat by pumping it top the atmosphere.  The growth of data collection and number of data centers is growing rapidly and the growth has no end end in sight so, by some accounts, this is a problem that is compounding.

You keep saying that data centers use 30-60% of power to eliminate wasted heat, unless they go to the Artic where data transmission become a problem.

But although these figures can be reached by old generation data centers, there are some alternative ways of reducing
power overhead that is used in modern data centers.
For example, the large Facebook data center of Prineville has a PUE of only 1.07  (only 7% overhead)
https://www.facebook.com/notes/facebook-engineering/designing-a-very-efficient-data-center/10150148003778920

In the computer center that I run, with more than 2000 Xeon cores, we have a PUE of less than 1.04 (and this is at latitude 45 deg,  not in the Artic)
right where we work.  The cooling is made, as in the Facebook data center with  direct air cooling and water evaporation for
the  warmest days.


Quote
Fraunhofer estimates the cost to optimize chips to run hot and fast are by no means insurmountable.

You keep mentioning your  Fraunhofer contract  as a validation for your project, but it is very unclear what exactly is your Fraunhofer contract.

It is well established that  there is a current research for  increasing the  running temperature of the computer chips. This is a way to reduce the cost
of cooling the computer centers by letting them run at higher temperature. This has nothing to do with your present project, which is running on purpose the
cpu to high temperatures to heat habitations.

Thanks for the thoughts Jacques and great news on you 1.04 PUE!  That is really impressive and certainly shows some datacenter efficiency chops.  The problem is a 1.04 PUE is a unicorn in the overall data center market.  The vast majority of datacenters are nowhere near that operating efficiency as evidenced by this really well researched and cited report by the NRDC - take a look at page 31 and you'll see that vast majority of energy consumption in Datacenters is in the 1.8 to 2.0 PUE.  Perhaps you can explain what a 2.0 PUE actually represents in operating efficiency to the forum? That might be the quickest way to illustrate the 30-60% number, PUE is a pretty hard metric to understand for the uninitiated.  NRDC: https://www.nrdc.org/energy/files/data-center-efficiency-assessment-IP.pdf

Thank you for bringing up Prineville - that is (was) a truly cutting edge data center.  My former company, PECI, was part of the prineville project and my good friend and former colleague authored and presented this paper on the project - I'd have to ask but I'm pretty sure he presented with the Facebook engineers:  http://aceee.org/files/proceedings/2012/data/papers/0193-000421.pdf-000421.pdf[/url] At the time Facebook's leased data centers had an average PUE of 1.5 and best practice and state of the art were running 1.3 PUE and 1.2 PUE, respectively.  So it is really impressive that you are hitting a 1.04.

As far as Fraunhofer is concerned, we are teamed on a couple of R&D proposals with them, NREL and Notre Dame - we are not under any contract, kind of a weird assumption.  No, you can't see the proposals and again... we're really not looking for your approval.   :D

Can you point me to some information on your Datacenter performance or methodology? I'd be really interested to see how you are managing a 1.04 PUE!
« Last Edit: October 19, 2015, 02:08:14 am by ltorsini »
 

Offline ltorsini

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Re: Exergy, another Bullshit "save the world" project
« Reply #67 on: October 18, 2015, 07:02:10 am »
What about the problem of heat requirements fluctuating over short periods of time?  For example, my family's greenhouses need almost no additional heat during even the coldest winter days due to incoming solar radiation, but may need massive heat (as much as 1MW) on a cold winter night  Could this match any kind of computation demand?

Even my own well-insulated house built in 1998 has a heat loss in excess of 15KW at the lowest outdoor temperatures.  Do you plan to stage computation up and down to match heat requirements?

Great question.  We're using a phase change thermal storage system that acts like a thermal battery to help ride through these typical fluctuations.  This way you can run the computation at a relatively flat performance profile and use the stored thermal energy to meet fluctuating demands.  Coupled with refrigeration/AC and DHW loads we're hoping to see a pretty even seasonal compute load.
« Last Edit: October 19, 2015, 02:07:38 am by ltorsini »
 

Offline dfmischler

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Re: Exergy, another Bullshit "save the world" project
« Reply #68 on: October 18, 2015, 05:07:59 pm »
Great question.  We're using a phase change thermal storage system that acts like a thermal battery to help ride through these typical fluctuations.  This way you can run the computation at a relatively flat performance profile and use the stored thermal energy to meet fluctuating demands.  Coupled with refrigeration/AC and DHW loads we're hoping to see a pretty even seasonal compute load.

Really.  How many megajoules per cubic meter do you think you can store?  At what cost?
 

Offline JacquesBBB

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Re: Exergy, another Bullshit "save the world" project
« Reply #69 on: October 18, 2015, 09:47:30 pm »
Can you point me to some information on your Datacenter performance or methodology? I'd be really interested to see how you are managing a 1.04 PUE!

The technology is SGI ICE cube air  containers.
http://www.ansys.stuba.sk/2011/pdf/SGI/ICE%20CUBE%20AIR_4274.pdf

Our PUE is even better than 1.04 over the full year. I did not check the latest data.
 

Offline ltorsini

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Re: Exergy, another Bullshit "save the world" project
« Reply #70 on: October 19, 2015, 01:23:51 am »
Great question.  We're using a phase change thermal storage system that acts like a thermal battery to help ride through these typical fluctuations.  This way you can run the computation at a relatively flat performance profile and use the stored thermal energy to meet fluctuating demands.  Coupled with refrigeration/AC and DHW loads we're hoping to see a pretty even seasonal compute load.

Really.  How many megajoules per cubic meter do you think you can store?  At what cost?

The fatty acid/fatty ester material we are using currently stores ~62.5 kBtu/gallon - we're under NDA with the manufacturer so we can't say much more about the material.
 

Offline ltorsini

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Re: Exergy, another Bullshit "save the world" project
« Reply #71 on: October 19, 2015, 01:37:58 am »
Can you point me to some information on your Datacenter performance or methodology? I'd be really interested to see how you are managing a 1.04 PUE!

The technology is SGI ICE cube air  containers.
http://www.ansys.stuba.sk/2011/pdf/SGI/ICE%20CUBE%20AIR_4274.pdf

Our PUE is even better than 1.04 over the full year. I did not check the latest data.

Yep, evaporatively cooled - no magic there unless you are doing something special with the DX system? 

The reason I've mentioned data centers sited near the arctic circle (not hyperbole!) is, if you are running an ultra efficient datacenter (1.04 counts) that is not using 100% free cooling then you are likely are using potable water (your tech looks way too cookie cutter to be reusing wastewater?) to run the system.  This practice is still contributing to the large and growing problem associated with water cooled chillers and evaporative cooling.

By using the rapidly shrinking reserves of potable water on the planet and relying on the undervaluation of the water/energy nexus. Unfortunately your 1.04 PUE is really relying on economic efficiencies that are directly related to devaluing water and ignoring its energy content based on its requirement for life and health as a subsidized and regulated utility. Pumping, treating, storing and transporting water have very high energy cost that are not yet being passed down to the end user and, therefore, not well accounted for in PUE or the broader economy.

If you want to get closer to numbers that represent the full impacts of computing I would suggest trying Energy Reuse Effectiveness (ERE) instead of PUE.  See page 8 of this Green Grid paper: http://www.thegreengrid.org/~/media/WhitePapers/ERE_WP_101510_v2.pdf   an page 11: "The concept and application of PUE has been beneficial to the industry but also challenging on occasion, due to misuse. ERE is a more precisely defined metric than PUE was in its first white paper."  ERE helps define the value of used and recovered energy on and off the datacenter, NREL and Notre Dame have both been involved in the development of ERE.

CA datacenters are already under fire for water consumption, here is a (somewhat) positive article on the topic, there are many negative articles begining to circulate: http://www.bloombergview.com/articles/2015-06-30/let-data-centers-have-their-water I can't imagine how datacenters are going to come under scrutiny in parts of Asia/India where potable water is already a major issue.

By comparison, the system we envision does not use water for cooling - it uses existing heating loads for cooling - so there is no associated water use in the design.  There is also less water use in the macro because we can eliminate the single use of electricity (and the power plant cooling costs associated) for compute or heat. There is actually a reason it is called Project Exergy.
« Last Edit: October 19, 2015, 03:43:02 am by ltorsini »
 

Offline dfmischler

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Re: Exergy, another Bullshit "save the world" project
« Reply #72 on: October 19, 2015, 08:53:59 pm »
Really.  How many megajoules per cubic meter do you think you can store?  At what cost?

The fatty acid/fatty ester material we are using currently stores ~62.5 kBtu/gallon - we're under NDA with the manufacturer so we can't say much more about the material.

One presumes that the phase change temperature of this material is one of the reasons that you need your computation devices to run hot.
 

Offline crispy_tofu

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Re: Exergy, another Bullshit "save the world" project
« Reply #73 on: October 19, 2015, 09:34:17 pm »
Quote
Taken from actual prototypes that made the ultimate sacrificed in the quest for change! As we melt them, you get them based on the time you pledge. Mounted, signed and dated by the Team, these parts should make one heck of a conversation piece!

So a melted computer part... for $1000.  :o (It'll make a great conversation with my pet rock lol  :'( )

When I could buy two entire life works of salvaged parts for that price (and some of them work, too!)...
(referring to EEVBlog #737 - World's Biggest Collection Of Electronics Components)
 

Offline ltorsini

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Re: Exergy, another Bullshit "save the world" project
« Reply #74 on: October 19, 2015, 11:43:08 pm »
Really.  How many megajoules per cubic meter do you think you can store?  At what cost?

The fatty acid/fatty ester material we are using currently stores ~62.5 kBtu/gallon - we're under NDA with the manufacturer so we can't say much more about the material.

One presumes that the phase change temperature of this material is one of the reasons that you need your computation devices to run hot.

dfmischler,

The temperature we're looking to achieve is related to the heat loads we're targeting, not the phase change material.  The PCM manufacturer can tailor the temperature to meet a fairly broad set of temperature requirements.
 


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