<html><head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
</head>
<body>
<p>Indeed. There's another point that's been missed in the
"superconductor" suggestion: Why do we get the heat in the first
place?</p>
<p>Superconductors are great when it comes to reducing resistive
losses in long and / or high current conductors (power
distribution, MRI magnets, ...). But this isn't why computer chips
get hot. Let me take you back to your Physics 101 when you learned
that Power P was the product of current I and voltage V. A logic
chip like a CPU is nothing but an assortment of gazillions of
little switches. When a switch is open, it may have voltage across
it but no current flows: no power gets dissipated. If it's closed,
current may flow but there won't be any voltage across it. Also
not a source of power loss. <br>
</p>
<p>The power loss (heat generation) happens when the little switches
are switching, i.e., when they are between open and closed and
when there is both a bit of voltage and a bit of current present.
Naively you might say that a switch is either on or off, and so
that shouldn't occur, but in both theory and practice, an
instantaneous loss-free switching process requires a signal of
infinite bandwidth when subjected to Fourier analysis. Fourier
analysis allows us to model any signal as a combination of
sinusoidal signals of different frequency, amplitude and phase,
and it's in particular the high-and-in-the-direction-of-infinity
frequency components of that combination that are needed for the
"ïnstantaneous"switching. Unfortunately, in any real circuit of
larger than zero size, reactive elements (capacitive and inductive
components or parasitic properties of that nature) attenuate
these. So the only real switching we can actually do in real life
is switching that dissipates power when it happens - no matter
whether the chip is built using superconductors or not.</p>
<p>In a modern CPU, a significant percentage of gates are this this
"gray" in-between state between 0 and 1 for a significant part of
the time, which is why you need elaborate cooling fans and water
coolers etc., and it's also why clock frequencies haven't
increased substantially in recent years. <br>
</p>
<div class="moz-cite-prefix">On 21/04/2023 12:06 am, Dave
Collier-Brown via Starlink wrote:<br>
</div>
<blockquote type="cite" cite="mid:b50e881f-ccad-caa0-7f9e-ab6bbd604cf1@indexexchange.com">
<p>Another point they missed: on earth, we can use conductive
cooling and transfer the heat from the machines to a flow of
air. In space, we can only use radiative cooling, and we need
to be out of the sun to have enough temperature difference.</p>
<p>--dave<br>
</p>
<div class="moz-cite-prefix">On 4/20/23 07:10, Hesham ElBakoury
via Starlink wrote:<br>
</div>
<blockquote type="cite" cite="mid:CAFvDQ9rDML2NGD09=mOTJ_g34obP+3_oz=z+NQUyxQCgUgHGeQ@mail.gmail.com">
<div dir="auto">The article about the ASCEND project says:
<div dir="auto">"Very low ambient temperatures in space will
dramatically reduce the need for cooling equipment that
consumes enormous amounts of energy. A significant part of a
data center’s energy use is for cooling equipment,
accounting for more than 50% in some facilities.
Temperatures can be as low as -292°F (-180°C) when an
orbiting object is in the Earth’s shadow."</div>
<div dir="auto"><br>
</div>
<div dir="auto">Hesham</div>
</div>
<br>
<div class="gmail_quote">
<div dir="ltr" class="gmail_attr">On Wed, Apr 19, 2023, 10:44
PM Daniel Schien <<a href="mailto:Daniel.Schien@bristol.ac.uk" moz-do-not-send="true" class="moz-txt-link-freetext">Daniel.Schien@bristol.ac.uk</a>>
wrote:<br>
</div>
<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex">
<div>
<div dir="auto">I assume any object in orbit will be
hidden from the sun some of the time. So, the machines
will require some pretty big battery to go up with
them. </div>
<div dir="auto"><br>
</div>
<div dir="auto">I'd like to also know what the launch cost
is. </div>
<div dir="auto"><br>
</div>
<div dir="auto">Tom Segert estimates in his LinkedIn post,
for a<span style="color:rgb(0,0,0);font-size:medium;background-color:rgb(255,255,255);display:inline!important"> 100kg
satellite payload:</span></div>
<div dir="auto"><br>
</div>
<div dir="auto">"TL:DR ~57 ton CO2e for a typical ESA
satellite (including Ariane 6 launch), <15t CO2e for
a satellite built in a factory and launched with a
re-usable rocket."</div>
<div dir="auto"><br>
</div>
<div dir="auto">Depending on the type of server that
should go up there, this is a fair amount of carbon to
offset from brighter sunlight.</div>
<div dir="auto"><br>
</div>
<div dir="auto">The article also gets the carbon footprint
wrong:</div>
<div dir="auto"><br>
</div>
<div dir="auto">"<span style="color:rgb(25,25,25);font-family:MajritTxRoman,serif;font-size:19px;letter-spacing:-0.01904px;background-color:rgb(255,255,255);display:inline!important">Data
centers are big energy consumers – between 2% and 3%
of all global consumption – a rate that is doubling
every year."</span></div>
<div dir="auto"><span style="color:rgb(25,25,25);font-family:MajritTxRoman,serif;font-size:19px;letter-spacing:-0.01904px;background-color:rgb(255,255,255);display:inline!important"><br>
</span></div>
<div dir="auto"><span style="color:rgb(25,25,25);font-family:MajritTxRoman,serif;font-size:19px;letter-spacing:-0.01904px;background-color:rgb(255,255,255);display:inline!important">The
latest was IEA estimating it to be around 220-320 TWh
(out of 30,000) in 2021 data and growing between
10-60% over 6 years in total (so let's than 10 CAGR).
But it's certainly not doubling every year. That's
just completely wrong.</span></div>
<div dir="auto"><br>
</div>
<div id="m_-5278516010422486526ms-outlook-mobile-signature" dir="auto">
<div><br>
</div>
<table style="border-spacing:0px;font-size:medium;font-family:Arial;line-height:1.5">
<tbody>
<tr>
<td>
<table>
<tbody>
<tr>
<td style="vertical-align:middle">
<h3 color="#000000" style="font-size:12px;margin:0px;color:black"><span>Daniel</span><span> </span><span>Schien</span></h3>
<p color="#000000" style="font-size:11px;margin:0px;line-height:22px;color:black">
<span>Senior Lecturer in Computer
Science</span></p>
<p color="#000000" style="font-size:11px;font-weight:500;margin:0px;line-height:22px;color:black"><span>Department
of Computer Science</span><span> | </span><span>University
of Bristol</span></p>
</td>
<td width="30"><br>
</td>
<td width="30"><br>
</td>
<td style="vertical-align:middle">
<table>
<tbody>
<tr style="vertical-align:middle" height="25">
<td colspan="2" style="vertical-align:middle">
<p color="#000000" style="font-size:14px;margin:0px;line-height:22px;color:black">
<span><b>Submit software
engineering project ideas
for 2022</b></span></p>
</td>
</tr>
<tr style="vertical-align:middle" height="25">
<td style="vertical-align:middle" width="30">
<table>
<tbody>
<tr>
<td style="vertical-align:bottom"><span width="11" style="display:block;background-color:rgb(84,158,242)"><br>
</span></td>
</tr>
</tbody>
</table>
</td>
<td><a color="#000000" style="font-size:11px;color:black" rel="noreferrer" moz-do-not-send="true"><span>http://bris.ac.uk/software-engineering</span></a><br>
<span style="font-size:9pt">Watch: </span><a href="https://youtu.be/lU-ZsBDFWDI" rel="noopener noreferrer
noreferrer" style="font-size:14.67px;font-family:Calibri,sans-serif;margin:0px;background-color:white" target="_blank" moz-do-not-send="true"><span style="font-size:9pt;margin:0px" lang="fr">https://youtu.be/lU-ZsBDFWDI</span></a></td>
</tr>
<tr style="vertical-align:middle" height="25">
<td style="vertical-align:middle" width="30">
<table>
<tbody>
<tr>
<td style="vertical-align:bottom"><span width="11" style="display:block;background-color:rgb(84,158,242)"><br>
</span></td>
</tr>
</tbody>
</table>
</td>
<td><span color="#000000" style="font-size:12px;color:black"><span>Merchant
Venturers Building ,
Woodland Rd Bristol, BS8 1UB</span></span></td>
</tr>
</tbody>
</table>
</td>
</tr>
</tbody>
</table>
</td>
</tr>
<tr>
<td>
<table style="width:683px">
</table>
</td>
</tr>
<tr>
<td width="30"><span style="height:8px;width:683px;box-sizing:border-box!important"><span style="font-size:9pt"><b>Book a meeting</b>: </span><a href="https://outlook.office365.com/owa/calendar/OfficeHours@bristol.ac.uk/bookings/" target="_blank" rel="noreferrer" moz-do-not-send="true"><span style="font-size:9pt">https://outlook.office365.com/owa/calendar/OfficeHours@bristol.ac.uk/booki</span></a></span></td>
</tr>
</tbody>
</table>
<br>
</div>
<hr style="display:inline-block;width:98%">
<div id="m_-5278516010422486526divRplyFwdMsg" dir="ltr"><font style="font-size:11pt" face="Calibri, sans-serif" color="#000000"><b>From:</b> E-impact <<a href="mailto:e-impact-bounces@ietf.org" target="_blank" rel="noreferrer" moz-do-not-send="true" class="moz-txt-link-freetext">e-impact-bounces@ietf.org</a>>
on behalf of Vint Cerf <vint=<a href="mailto:40google.com@dmarc.ietf.org" target="_blank" rel="noreferrer" moz-do-not-send="true" class="moz-txt-link-freetext">40google.com@dmarc.ietf.org</a>><br>
<b>Sent:</b> Thursday, April 20, 2023 2:16:38 AM<br>
<b>To:</b> <a href="mailto:tom@evslin.com" target="_blank" rel="noreferrer" moz-do-not-send="true" class="moz-txt-link-freetext">
tom@evslin.com</a> <<a href="mailto:tom@evslin.com" target="_blank" rel="noreferrer" moz-do-not-send="true" class="moz-txt-link-freetext">tom@evslin.com</a>><br>
<b>Cc:</b> Michael Richardson <<a href="mailto:mcr@sandelman.ca" target="_blank" rel="noreferrer" moz-do-not-send="true" class="moz-txt-link-freetext">mcr@sandelman.ca</a>>;
starlink <<a href="mailto:starlink@lists.bufferbloat.net" target="_blank" rel="noreferrer" moz-do-not-send="true" class="moz-txt-link-freetext">starlink@lists.bufferbloat.net</a>>;
<a href="mailto:e-impact@ietf.org" target="_blank" rel="noreferrer" moz-do-not-send="true" class="moz-txt-link-freetext">
e-impact@ietf.org</a> <<a href="mailto:e-impact@ietf.org" target="_blank" rel="noreferrer" moz-do-not-send="true" class="moz-txt-link-freetext">e-impact@ietf.org</a>><br>
<b>Subject:</b> Re: [E-impact] [Starlink] DataCenters
in Space (was Re: fiber IXPs in space)</font>
<div> </div>
</div>
<div>
<div dir="ltr">O&M will be a bear
<div>v</div>
<div><br>
</div>
</div>
<br>
<div>
<div dir="ltr">On Wed, Apr 19, 2023 at 9:13 PM Tom
Evslin via Starlink <<a href="mailto:starlink@lists.bufferbloat.net" target="_blank" rel="noreferrer" moz-do-not-send="true" class="moz-txt-link-freetext">starlink@lists.bufferbloat.net</a>>
wrote:<br>
</div>
<blockquote style="margin:0px 0px 0px
0.8ex;border-left:1px solid
rgb(204,204,204);padding-left:1ex">
I think space-based data centers will be the rule
rather than the exception. Wrote about that a couple
of years ago although, as usual, things have not
happened as quickly as I predicted
<a href="https://blog.tomevslin.com/2021/07/computing-clouds-in-orbit-a-possible-roadmap.html" rel="noreferrer noreferrer" target="_blank" moz-do-not-send="true" class="moz-txt-link-freetext">
https://blog.tomevslin.com/2021/07/computing-clouds-in-orbit-a-possible-roadmap.html</a><br>
<br>
-----Original Message-----<br>
From: Starlink <<a href="mailto:starlink-bounces@lists.bufferbloat.net" target="_blank" rel="noreferrer" moz-do-not-send="true" class="moz-txt-link-freetext">starlink-bounces@lists.bufferbloat.net</a>>
On Behalf Of Michael Richardson via Starlink<br>
Sent: Wednesday, April 19, 2023 7:35 PM<br>
To: starlink <<a href="mailto:starlink@lists.bufferbloat.net" target="_blank" rel="noreferrer" moz-do-not-send="true" class="moz-txt-link-freetext">starlink@lists.bufferbloat.net</a>>;
<a href="mailto:e-impact@ietf.org" target="_blank" rel="noreferrer" moz-do-not-send="true" class="moz-txt-link-freetext">
e-impact@ietf.org</a><br>
Subject: [Starlink] DataCenters in Space (was Re:
fiber IXPs in space)<br>
<br>
<br>
I saw this reported in BIS-Spaceflight.<br>
(I'm usually a few months behind in reading it) I
like the "first objective"!<br>
<br>
<a href="https://www.thalesgroup.com/en/worldwide/space/press-release/ascend-thales-alenia-space-lead-european-feasibility-study-data" rel="noreferrer noreferrer" target="_blank" moz-do-not-send="true" class="moz-txt-link-freetext">https://www.thalesgroup.com/en/worldwide/space/press-release/ascend-thales-alenia-space-lead-european-feasibility-study-data</a><br>
<br>
Cannes, November 14, 2022 – Thales Alenia Space, the
joint company between Thales (67%) and Leonardo
(33%), has been chosen by the European Commission to
lead the ASCEND (Advanced Space Cloud for European
Net zero emission and Data sovereignty) feasibility
study for data centers in orbit, as part of Europe’s
vast Horizon Europe research program.<br>
<br>
Digital technology’s expanding environmental
footprint is becoming a major<br>
challenge: the burgeoning need for digitalization
means that data centers in Europe and around the
world are growing at an exponential pace, which in
turn has a critical energy and environmental impact.<br>
<br>
The first objective of this study will be to assess
if the carbon emissions from the production and
launch of these space infrastructures will be
significantly lower than the emissions generated by
ground-based data centers, therefore contributing to
the achievement of global carbon neutrality. The
second objective will be to prove that it is
possible to develop the required launch solution and
to ensure the deployment and operability of these
spaceborne data centers using robotic assistance
technologies currently being developed in Europe,
such as the EROSS IOD demonstrator.<br>
<br>
This project is expected to demonstrate to which
extent space-based data centers would limit the
energy and environmental impact of their ground
counterparts, thus allowing major investments within
the scope of Europe’s Green Deal, possibly
justifying the development of a more
climate-friendly, reusable heavy launch vehicle.
Europe could thus regain its leadership in space
transport and space logistics, as well as the
assembly and operations of large infrastructures in
orbit.<br>
<br>
_______________________________________________<br>
Starlink mailing list<br>
<a href="mailto:Starlink@lists.bufferbloat.net" target="_blank" rel="noreferrer" moz-do-not-send="true" class="moz-txt-link-freetext">Starlink@lists.bufferbloat.net</a><br>
<a href="https://lists.bufferbloat.net/listinfo/starlink" rel="noreferrer noreferrer" target="_blank" moz-do-not-send="true" class="moz-txt-link-freetext">https://lists.bufferbloat.net/listinfo/starlink</a><br>
<br>
_______________________________________________<br>
Starlink mailing list<br>
<a href="mailto:Starlink@lists.bufferbloat.net" target="_blank" rel="noreferrer" moz-do-not-send="true" class="moz-txt-link-freetext">Starlink@lists.bufferbloat.net</a><br>
<a href="https://lists.bufferbloat.net/listinfo/starlink" rel="noreferrer noreferrer" target="_blank" moz-do-not-send="true" class="moz-txt-link-freetext">https://lists.bufferbloat.net/listinfo/starlink</a><br>
</blockquote>
</div>
<br clear="all">
<div><br>
</div>
<span>-- </span><br>
<div dir="ltr">
<div dir="ltr">
<div>Please send any postal/overnight deliveries to:</div>
<div>
<div>Vint Cerf</div>
<div>Google, LLC</div>
<div>1900 Reston Metro Plaza, 16th Floor</div>
<div>Reston, VA 20190</div>
<div>+1 (571) 213 1346<br>
</div>
<div><br style="color:rgb(34,34,34)">
</div>
</div>
<div><br>
</div>
<div>until further notice</div>
<div><br>
</div>
<div><br>
</div>
<div><br>
</div>
</div>
</div>
</div>
</div>
-- <br>
E-impact mailing list<br>
<a href="mailto:E-impact@ietf.org" target="_blank" rel="noreferrer" moz-do-not-send="true" class="moz-txt-link-freetext">E-impact@ietf.org</a><br>
<a href="https://www.ietf.org/mailman/listinfo/e-impact" rel="noreferrer noreferrer" target="_blank" moz-do-not-send="true" class="moz-txt-link-freetext">https://www.ietf.org/mailman/listinfo/e-impact</a><br>
</blockquote>
</div>
<br>
<fieldset class="moz-mime-attachment-header"></fieldset>
<pre class="moz-quote-pre" wrap="">_______________________________________________
Starlink mailing list
<a class="moz-txt-link-abbreviated moz-txt-link-freetext" href="mailto:Starlink@lists.bufferbloat.net" moz-do-not-send="true">Starlink@lists.bufferbloat.net</a>
<a class="moz-txt-link-freetext" href="https://lists.bufferbloat.net/listinfo/starlink" moz-do-not-send="true">https://lists.bufferbloat.net/listinfo/starlink</a>
</pre>
</blockquote>
<pre class="moz-signature" cols="72">--
David Collier-Brown, | Always do right. This will gratify
System Programmer and Author | some people and astonish the rest
<a class="moz-txt-link-abbreviated moz-txt-link-freetext" href="mailto:dave.collier-brown@indexexchange.com" moz-do-not-send="true">dave.collier-brown@indexexchange.com</a> | -- Mark Twain</pre>
<br>
<p><strong><em><span style="color: #212121;">CONFIDENTIALITY
NOTICE AND DISCLAIMER</span></em></strong><em><span style="color: #212121;"> : This telecommunication, including
any and all attachments, contains confidential information
intended only for the person(s) to whom it is addressed. Any
dissemination, distribution, copying or disclosure is
strictly prohibited and is not a waiver of confidentiality.
If you have received this telecommunication in error, please
notify the sender immediately by return electronic mail and
delete the message from your inbox and deleted items
folders. This telecommunication does not constitute an
express or implied agreement to conduct transactions by
electronic means, nor does it constitute a contract offer, a
contract amendment or an acceptance of a contract offer.
Contract terms contained in this telecommunication are
subject to legal review and the completion of formal
documentation and are not binding until same is confirmed in
writing and has been signed by an authorized signatory.</span></em></p>
<br>
<fieldset class="moz-mime-attachment-header"></fieldset>
<pre class="moz-quote-pre" wrap="">_______________________________________________
Starlink mailing list
<a class="moz-txt-link-abbreviated" href="mailto:Starlink@lists.bufferbloat.net">Starlink@lists.bufferbloat.net</a>
<a class="moz-txt-link-freetext" href="https://lists.bufferbloat.net/listinfo/starlink">https://lists.bufferbloat.net/listinfo/starlink</a>
</pre>
</blockquote>
<pre class="moz-signature" cols="72">--
****************************************************************
Dr. Ulrich Speidel
School of Computer Science
Room 303S.594 (City Campus)
The University of Auckland
<a class="moz-txt-link-abbreviated" href="mailto:u.speidel@auckland.ac.nz">u.speidel@auckland.ac.nz</a>
<a class="moz-txt-link-freetext" href="http://www.cs.auckland.ac.nz/~ulrich/">http://www.cs.auckland.ac.nz/~ulrich/</a>
****************************************************************
</pre>
</body>
</html>