About elkement (Elke Stangl)

Physicist, engineer, geek, dilettante science blogger, IT security consultant, search term poet, Subversive El(k)ement.

The Subtle Power of the Top Snippet. A New Sub-Genre of Google Poetry.

New game, new rules!

I have tried to make the rules tougher! Here is some context and history.

  1. Search for your site on Google: site:elkement.blog
  2. Pick the first search result in the language of your site[*]
  3. Pick a chain of words, a contiguous snippet from this Google search result. This becomes the title of your poem.
  4. Copy your chosen snippet and search again, now for this phrase.
  5. Pick the first snippet from the new search results, choose a phrase. This is the next line of the poem; re-arrangement, editing or skipping search results is not allowed.
  6. Goto 4.

[*] The major challenge in this game is one strange attractor: All the poetic chaos is finally is sucked into this black-hole: Dictionaries and thesauruses. I’ve used a private browser window with both preferred language and display language set to English. Yet Google knows my IP address and keeps showing me translations to German as the first search result.

Unless you want to pick a term like German-English translation, your worm-hole out of the dictionary attractor is the innocuous reference to the web page in Cache. Fortunately, when searching for Cache there was a ‘reasonable’ English snippet on the first results page, and I felt entitled to choose it, according to rule 2. The poem shows that I was stuck in the potential well of the cache. The same happened with less severe attractors, and eerily enough these events always had a self-referential flavor. I was also leading and pacing, leading and pacing, leading and pacing… until I was in sync. And the pop-up, pop-up, pop-up was hard to get rid of, as in the real world.

I also had to appeal to Google themselves, and the poem describes itself correctly as a treasure hunting game – to find hidden objects or places.

Enough of the meta-analysis and over-explanations, this is no Worstward Ho!

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Combine Just Anything

your transactions are now in one beautiful place
anywhere in Europe

search engine for
facts and stats. Oh and Gifs

Reaction
Adverse reaction
Cache
Cache
Cache
Cache
How to clear
If you don’t want a record

switch to another program
You don’t have to close
The Virus of Life

I am your disease
I’ll invade all your thoughts
I want governance of all worlds

negotiating responses to problems
strategies to solve
The comprehensive nature of the list

all elements or aspects of something
denoting a system of
powers of ten

people both nationally and internationally
gain real credibility
as content creators can attest

state that something is true or real
of a satisfactory standard
engaged for an indefinite period

sentences containing
gold coins

Canadian Maple Leafs
and Backdates
To mark or supply
Trailers for Sale

a leading provider
leading
Pacing and Leading
Pacing and Leading
Pacing and Leading
Cache

fix issues
Cache
temporarily stores
temporary stores
Pop-up-Store
Pop-up-Store
pop up
pɒpˌʌp

a treasure hunting game
find hidden objects or places
throughout hundreds of custom designed maps
in just a few seconds
a few seconds
a few
‎Quite a few

translate.google
Google

Day 10 of the Doodle
a fluttering glimpse of today’s action

hoping to prove themselves best in class
With such fierce competition
Im Cache

Random image, first thing I saw in my media collection now.

Bots, Like This! I am an Ardent Fan of HTTPS and Certificates!

This is an experiment in Machine Learning, Big Data, Artificial Intelligence, whatever.

But I need proper digression first.

Last autumn, I turned my back on social media and went offline for a few days.

There, in that magical place, the real world was offline as well. A history of physics museum had to be opened, just for us.

The sign says: Please call XY and we open immediately.

Scientific instruments of the past have a strange appeal, steampunk-y, artisanal, timeless. But I could not have enjoyed it, hadn’t I locked down the gates of my social media fortresses before.

Last year’ improved’ bots and spammers seem to have invaded WordPress. Did their vigilant spam filters feel a disturbance of the force? My blog had been open for anonymous comments since more than 5 years, but I finally had to restrict access. Since last year every commentator needs to have one manually approved comment.

But how to get attention if I block the comments? Spam your links by Liking other blogs. Anticipate that clickers will be very dedicated: Clicking on your icon only takes the viewer to your gravatar profile. The gravatar shows a link to the actual spammy website.

And how to pick suitable – likeable – target blog posts? Use your sophisticated artificial intelligence: If you want to sell SSL certificates (!) pick articles that contain key words like SSL or domain – like this one. BTW, I take the ads for acne treatment personally. Please stick to marketing SSL certificates. Especially in the era of free certificates provided by Let’s Encrypt.

Please use a different image for your different gravatars. You have done rather well when spam-liking the post on my domains and HTTPS, but what was on your mind when you found my post on hijacking orphaned domains for malvertizing?

Did statements like this attract the army of bots?

… some of the pages contain links to other websites that advertize products in a spammy way.

So what do I need to do to make you all like this post? Should I tell you that have a bunch of internet domains? That I migrated my non-blogs to HTTPS last year? That WordPress migrated blogs to HTTPS some time ago? That they use Let’s Encrypt certificates now, just as the hosting provider of my other websites does?

[Perhaps I should quote ‘SSL’ and ‘TLS’, too.]

Or should I tell you that I once made a fool of myself for publishing my conspiracy theories – about how Google ditched my blog from their index? While I actually had missed that you need to add the HTTPS version as a separate item in Google Webmaster Tools?

So I despearately need help with Search Engine Optimization and Online Marketing. Google shows me ads for their free online marketing courses on Facebook all the time now.

Or I need help with HTTPS (TLS/SSL) – embarrassing, as for many years I did nothing else than implementing Public Key Infrastructures and troubleshooting certificates? I am still debugging of all kinds weird certificate chaining and browser issues. The internet is always a little bit broken, says Sir Tim Berners-Lee.

[Is X.509 certificate a good search term? No, too nerdy, I guess.]

Or maybe you are more interested in my pioneering Search Term Poetry and Spam Poetry.  I need new raw material.

Like this! Like this! Like this!

Maybe I am going to even approve a comment and talk to you. It would not be the first time I fail the Turing test on this blog.

Don’t let me down, bots! I count on you!

Update 2018-02-13: So far, this post was a success. The elkemental blog has not seen this many likes in years.… and right now I noticed that the omnipresent suit bot also started to market solar energy and to like my related posts!

Update 2018-02-18: They have not given up yet – we welcome another batch of bots!

bots-welcome-experiment-success-2

The Heat Source Paradox

It is not a paradox – it is a straight-forward relation between a heat pump system’s key data:

The lower a heat pump’s performance factor is, the smaller the source can be built.

I would not write this post, hadn’t I found a version of this statement with a positive twist  used in an advert!

In this post I consider a heat pump a blackbox that converts input energy into output heat energy – it ‘multiplies’ energy by a performance factor. A traditional mechanical heat pump uses electrical input energy to drive a mechanical compressor. The uncommon Rotation Heat Pump utilizes the pressure gradient created by centrifugal forces and thus again by electrical power.

But a pressure difference can also be maintained by adsorption/desorption processes or by changing the amount of one fluid dissolved in another; Einstein’s famous refrigerator uses a more complex combination of such dissolution/evaporation processes. Evaporation or desorption can be directly driven by heat: A gas heat pump thus ‘multiplies’ the energy from burning natural gas (and in addition, a heat pump and a gas boiler can be combined in one unit).

The overall performance factor of a gas heat pump – kWh heating energy out over kWh gas in – is about 1,5 – 2. This is lower than 4 – 5 available with mechanical compressors. But the assessment depends on the costs of kWh gas versus kWh electrical energy: If gas is four times cheaper (which nearly is the case in Germany) than burning natural gas in a traditional boiler without any ‘heat pump multiplication’, then the classical boiler can be more economical than using a heat pump with an electrical compressor. If gas is ‘only’ two times as cheap, then a gas heat pump with an overall performance number of ‘only’ 2 will still beat an electrical heat pump with a performance factor of 4.

While the gas heat pump may have its merits under certain market conditions, its performance number is low: For one kWh of gas you only get two kWh of heating energy. This  means you only need to provide one kWh of ‘ambient’ energy from your source – geothermal, water, or air. If the performance factor of an electrical heat pump is 4, you multiply each kWh of input energy by 4. But the heat source has to be able to supply the required 3 kWh. This is the whole ‘paradox’: The better the heat pump’s performance is in terms of heating energy over input energy, the more energy has to be released by a properly designed heat source, like ground loops sufficiently large, a ground-water well providing sufficient flow-rate, an air heat pump’s ventilator powerful enough, or our combination of a big enough solar/air collector plus water tank.

Illustration of the ‘heat source paradox’: The lower the performance number (ratio of output and input energy), the lower is the required ambient energy that has to be provided by ‘the environment’. The output heating energy in red is the target number that has to be met – it is tied to the building’s design heat load.

If you wish to state it that way, a heat pump with inferior performance characteristics has the ‘advantage’ that the source can be smaller – less pipes to be buried in the ground or a smaller water tank. And in an advert for a gas heat pump I found it spelled out exactly in this way, as a pro argument compared to other heat pumps:

The heat source can be built much smaller – investment costs are lower!

It is not wrong, but it is highly misleading. It is like saying that heating electrically with a resistive heating element – and thus a performance number of 1 – is superior because you do not need to invest in building any source of ambient energy at all.

Things You Find in Your Hydraulic Schematic

Building an ice storage powered heat pump system is a DIY adventure – for a Leonardo da Vinci of plumbing, electrical engineering, carpentry, masonry, and computer technology.

But that holistic approach is already demonstrated clearly in our hydraulic schematics. Actually, here it is even more daring and bold:

There is Plutonium – Pu – everywhere in the heating circuit and the brine circuit …

I can’t tell if this is a hazard or if it boosts energy harvest. But I was not surprised – given that Doc Emmett Brown is our hero:

Maybe we see the impact of contamination already: How should I explain the mutated butterflies with three wings otherwise? After all, they are even tagged with M

Our default backup heating system is … Facebook Messenger!

So the big internet companies are already delivering heating-as-a-service-from-the-cloud!

But what the hell is the tennis ball needed for?

 

Cooling Potential

I had an interesting discussion about the cooling potential of our heat pump system – in a climate warmer than ours.

Recently I’ve shown data for the past heating season, including also passive cooling performance:

After the heating season, tank temperature is limited to 10°C as long as possible – the collector is bypassed in the brine circuit (‘switched off’). But with the beginning of May, the tank temperature starts to rise though as the tank is heated by the surrounding ground.

Daily cooling energy hardly exceeds 20kWh, so the average cooling power is always well below 1kW. This is much lower than the design peak cooling load – the power you would need to cool the rooms to 20°C at noon on a hot in summer day (rather ~10kW for our house.)

The blue spikes are single dots for a few days, and they make the curve look more impressive than it really is: We could use about 600kWh of cooling energy – compared to about 15.000kWh for space heating. (Note that I am from Europe – I use decimal commas and thousands dots :-))

There are three ways of ‘harvesting cold’ with this system:

(1) When water in the hygienic storage tank (for domestic hot water) is heated up in summer, the heat pump extracts heat from the underground tank.

Per summer month the heat pump needs about 170kWh of input ambient energy from the cold tank – for producing an output heating energy of about 7kWh per day – 0,3kW on average for two persons, just in line with ‘standards’. This means that nearly all the passive cooling energy we used was ‘produced’ by heating hot water.

You can see the effect on the cooling power available during a hot day here (from this article on passive cooling in the hot summer of 2015)

Blue arrows indicate hot water heating time slots – for half an hour a cooling power of about 4kW was available. But for keeping the room temperature at somewhat bearable levels, it was crucial to cool ‘low-tech style’ – by opening the windows during the night (Vent)

(2) If nights in late spring and early summer are still cool, the underground tank can be cooled via the collector during the night.

In the last season we gained about ~170kWh in total in that way – so only as much as by one month of hot water heating. The effect also depends on control details: If you start cooling early in the season when you ‘actually do not really need it’ you can harvest more cold because of the higher temperature difference between tank and cold air.

(3) You keep the cold or ice you ‘create’ during the heating season.

The set point tank temperature for summer  is a trade-off between saving as much cooling energy as possible and keeping the Coefficient of Performance (COP) reasonably high also in summer – when the heat sink temperature is 50°C because the heat pump only heats hot tap water.

20°C is the maximum heat source temperature allowed by the heat pump vendor. The temperature difference to the set point of 10°C translates to about 300kWh (only) for 25m3 of water. But cold is also transferred to ground and thus the effective store of cold is larger than the tank itself.

What are the options to increase this seasonal storage of cold?

  • Turning the collector off earlier. To store as much ice as possible, the collector could even be turned off while still in space heating mode – as we did during the Ice Storage Challenge 2015.
  • Active cooling: The store of passive cooling energy is limited – our large tank only contains about 2.000kWh even if frozen completely; If more cooling energy is required, there has to be a cooling backup. Some brine/water heat pumps[#] have a 4-way-valve built into the refrigeration cycle, and the roles of evaporator and condenser can be reversed: The room is cooled and the tank is heated up. In contrast to passive cooling the luke-warm tank and the surrounding ground are useful. The cooling COP would be fantastic because of the low temperature difference between source and sink – it might actually be so high that you need special hydraulic precautions to limit it.

The earlier / the more often the collector is turned off to create ice for passive cooling, the worse the heating COP will be. On the other hand, the more cold you save, the more economic is cooling later:

  1. Because the active cooling COP (or EER[*]) will be higher and
  2. Because the total cooling COP summed over both cooling phases will be higher as no electrical input energy is needed for passive cooling – only circulation pumps.

([*] The COP is the ratio of output heating energy and electrical energy, and the EER – energy efficiency ratio – is the ratio of output cooling energy and electrical energy. Using kWh as the unit for all energies and assuming condenser and evaporator are completely ‘symmetrical’, the EER or a heat pump used ‘in reverse’ is its heating COP minus 1.)

So there would be four distinct ways / phases of running the system in a season:

  1. Standard heating using collector and tank. In a warmer climate, the tank might not even be frozen yet.
  2. Making ice: At end of the heating season the collector might be turned off to build up ice for passive cooling. In case of an ’emergency’ / unexpected cold spell of weather, the collector could be turned on intermittently.
  3. Passive cooling: After the end of the heating season, the underground tank cools the buffer tank (via its internal heat exchanger spirals that containing cool brine) which in turn cools the heating floor loops turned ‘cooling loops’.
  4. When passive cooling power is not sufficient anymore, active cooling could be turned on. The bulk volume of the buffer tank is cooled now directly with the heat pump, and waste heat is deposited in the underground tank and ground. This will also boost the underground heat sink just right to serve as the heat source again in the upcoming heating season.

In both cooling phases the collector could be turned on in colder nights to cool the tank. This will work much better in the active cooling phase – when the tank is likely to be warmer than the air in the night. Actually, night-time cooling might be the main function the collector would have in a warmer climate.

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[#] That seems to be valid mainly/only for domestic brine-water heat pumps from North American or Chinese vendors; they offer the reversing valve as a common option. European vendors rather offer a so called Active Cooling box, which is a cabinet that can be nearly as the heat pump itself. It contains a bunch of valves and heat exchangers that allow for ‘externally’ swapping the connections of condenser and evaporator to heat sink and source respectively.

Reverse Engineering Fun

Recently I read a lot about reverse engineering –  in relation to malware research. I for one simply wanted to get ancient and hardly documented HVAC engineering software to work.

The software in question should have shown a photo of the front panel of a device – knobs and displays – augmented with current system’s data, and you could have played with settings to ‘simulate’ the control unit’s behavior.

I tested it on several machines, to rule out some typical issues quickly: Will in run on Windows 7? Will it run on a 32bit system? Do I need to run it was Administrator? None of that helped. I actually saw the application’s user interface coming up once, on the Win 7 32bit test machine I had not started in a while. But I could not reproduce the correct start-up, and in all other attempts on all other machines I just encountered an error message … that used an Asian character set.

I poked around the files and folders the application uses. There were some .xls and .xml files, and most text was in the foreign character set. The Asian error message was a generic Windows dialogue box: You cannot select the text within it directly, but the whole contents of such error messages can be copied using Ctrl+C. Pasting it into Google Translate it told me:

Failed to read the XY device data file

Checking the files again, there was an on xydevice.xls file, and I wondered if the relative path from exe to xls did not work, or if it was an issue with permissions. The latter was hard to believe, given that I simply copied the whole bunch of files, my user having the same (full) permissions on all of them.

I started Microsoft Sysinternals Process Monitor to check if the application was groping in vain for the file. It found the file just fine in the right location:

Immediately before accessing the file, the application looped through registry entries for Microsoft JET database drivers for Office files – the last one it probed was msexcl40.dll – a  database driver for accessing Excel files.

There is no obvious error in this dump: The xls file was closed before the Windows error popup was brought up; so the application had handled the error somehow.

I had been tinkering a lot myself with database drivers for Excel spreadsheets, Access databases, and even text files – so that looked like a familiar engineering software hack to me 🙂 On start-up the application created a bunch of XML files – I saw them once, right after I saw the GUI once in that non-reproducible test. As far as I could decipher the content in the foreign language, the entries were taken from that problematic xls file which contained a formatted table. It seemed that the application was using a sheet in the xls file as a database table.

What went wrong? I started Windows debugger WinDbg (part of the Debugging tools for Windows). I tried to go the next unhandled or handled exception, and I saw again that it stumbled over msexec40.dll:

But here was finally a complete and googleable error message in nerd speak:

Unexpected error from external database driver (1).

This sounded generic and I was not very optimistic. But this recent Microsoft article was one of the few mentioning the specific error message – an overview of operating system updates and fixes, dated October 2017. It describes exactly the observed issue with using the JET database driver to access an xls file:

Finally my curious observation of the non-reproducible single successful test made sense: When I started the exe on the Win 7 test client, this computer had been started the first time after ~3 months; it was old and slow, and it was just processing Windows Updates – so at the first run the software had worked because the deadly Windows Update had not been applied yet.

Also the ‘2007 timeframe’ mentioned was consistent – as all the application’s executable files were nearly 10 years old. The recommended strategy is to use a more modern version of the database driver, but Microsoft also states they will fix it again in a future version.

So I did not get the software to to run, as I obviously cannot fix somebody else’s compiled code – but I could provide the exact information needed by the developer to repair it.

But the key message in this post is that it was simply a lot of fun to track this down 🙂

Simulating Life-Forms (2): Cooling Energy

I found this comprehensive research report:
Energy Use in the Australian Residential Sector 1986–2020 (June 2008)
(several PDFs for download, click the link Energy Use… to display them)

There are many interesting results – and the level of detail is impressive: The authors modelled the energy used per appliance type, by e.g. factoring in how building types change slowly over time or by modelling the development of TV sets and their usage. Occupancy factors for buildings are determined from assumptions about typical usage profiles called Stay At Home, At Work or Night Owl.

I zoom in on simulating and predicting usage of air conditioning and thus cooling energy:

They went to great lengths to simulate the behavior of home owners to model operations of air conditioning and thus total cooling energy for a season, for a state or the whole country.

The authors investigated the official simulation software used for rating buildings (from …part2.pdf):

In the AccuRate software, once cooling is invoked the
program continues to assume that the occupant is willing to
tolerate less than optimal comfort conditions and will therefore terminate cooling if in the absence of such cooling the internal temperature would not rise above the summer neutral temperature noted in Table 57, + 2.5oC plus allowances for humidity and air movement as applicable. While this may be appropriate for rating purposes, it is considered to be an unlikely form of behaviour to be adopted by householders in the field and as such this assumption is likely to underestimate the potential space cooling demand. This theory is supported by the survey work undertaken by McGreggor in South Australia.

This confirms what I am saying all the time: The more modern a building is, or generally nowadays given ‘modern’ home owners’ requirements, the more important would it be to actually simulate humans’ behavior, on top of the physics and the control logic.

The research study also points out e.g. that AC usage has been on the rise, because units got affordable, modern houses are built with less focus on shading, and home owners demand higher standards of comfort. Ducted cooling systems that cover the cooling load of the whole house are being implemented, and they replace systems for cooling single zones only. Those ducted systems have a rated output cooling power greater than 10kW – so the authors (and it seems Australian governmental decision makers) are worried about the impact on the stability of the power grid on hot days [*].

Once AC had been turned on for the first time in the hot season, home owners don’t switch it off again when the theoretical ‘neutral’ summer temperature would be reached again, but they keep it on and try to maintain a lower temperature (22-23°C) that is about constant irrespective of temperature outside. So small differences in actual behavior cause huge error bars in total cooling energy for a season:

The impact of this resetting of the cooling thermostat operation was found to be significant. A comparison was undertaken between cooling loads determined using the AccuRate default thermostat settings and the modified settings as described above. A single-storey brick veneer detached dwelling with concrete slab on ground floor and ceiling insulation was used for the comparison. The comparison was undertaken in both the Adelaide and the Darwin climate zones. In Adelaide the modified settings produced an increased annual cooling load 64% higher than that using the AccuRate default settings.

The report also confirms my anecdotal evidence: In winter (colder regions) people heat rooms to higher temperatures than ‘expected’; in summer (warmer regions) people want to cool to a lower temperature:

This is perhaps not surprising, de Dear notes that: “preferred temperature for a particular building did not necessarily coincide with thermal neutrality, and this semantic discrepancy was most evident in HVAC buildings where preference was depressed below neutrality in warm climates and elevated above neutrality in cold climates (ie people preferred to feel cooler than neutral in warm climates, and warmer than neutral in cold climates)” (Richard de Dear et al 1997, P xi).

I noticed that the same people who (over-)heat their rooms to 24°C in winter might want to cool to 20°C in summer. In middle Europe AC in private homes has been uncommon, but I believe it is on the rise, too, also because home owners got accustomed to a certain level of cooling when they work in typical office buildings.

My conclusion is (yet again) that you cannot reliably ‘predict’ cooling energy. It’s already hard to do so for heating energy for low energy houses, but nearly impossible for cooling energy. All you can do – from a practical / system’s design perspective – is to make sure that there is an ‘infinite’ source of cooling energy available.

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[*] Edit: And it actually happenend in February 2017.