Migration – Bye Bye Hosteurope – Hello Amazon AWS

I recently moved this blog from one old server to a new one. This is my first blog post on this new server. Let’s hope nothing explodes.

For many years I have been a more or less happy customer of Hosteurope. It is a hosting company headquartered in Germany (with hosting sites in other European countries). Many years ago I chose to sign up with Hosteurope for one of their so called “VPS” aka Virtual Private Server. That’s basically a virtual server running on one of their larger server clusters.

About a year ago I realized that my annual bill for that Hosteurope server was about €156 per year. That’s not a huge amount, but as I’ve been involved in cloud-hosting for many of our projects, I knew there are many other options that offer a way better price / value ratio.

Being lazy as humans are, I didn’t want to migrate my server away. In fact, it would have been enough for me if Hosteurope would have lowered my service charge to the price of the currently available equivalent VPS they are selling. Over the years, hardware has gotten cheaper and so has hosting gotten cheaper. In short: Newer VPS products of Hosteurope now cost less and provide more power.

I simply love attractive cost/value ratios.

So last year I reached out to Hosteurope and asked them wether they can offer me my old VPS for the new price (~€4 less per month or so). It’s not that much of a difference, but for the principle of it: I just like to be treated fairly. They did not agree to that and simply said: “You have to stick to your old product, or you may also terminate your contract.” Last year I missed that deadline — again, that wasn’t really a priority for me — and therefore, the contract renewed for another year. This year, though, I remembered and terminated on time.

AWS has almost unlimited capabilities

For over 10 years our businesses are now customers at Amazon Web Services. We’ve been with them from almost their first service. So I’ve been working with AWS for a long long time. We even had an incident where we literally spent $4000 USD in minutes — accidentally. That can happen if you “overdo” extreme automation 🙂

However, when using AWS properly, it can be very useful and cost-efficient. Especially, when we’re talking about hosting my small blog kozen.de as well as some other sites I run on this server.

AWS has some great services I was able to use for this move. That includes their S3 Simple Storage, EC2 Elastic Cloud, CloudFront Content Delivery Network, CloudWatch Monitoring Service and many others well.

AWS’s own Amazon Linux 2 is also a great Linux distribution I’ve grown to like and I’m quite confident it keeps getting maintained for the next 10 years. The old Debian that was running on my Hosteurope server wasn’t being maintained by Hosteurope – especially as they had some funky customizations and source settings in there, which for the past years seem to not have gotten the love they deserved. Hence, I ended up with an outdated system.

I’m confident this will be better now. And besides, instead of paying €156 I’m expecting to pay at most €60 per year. That’s a fluffy 60% savings and I haven’t even factored in discounts at Reserved Instance costs.

Let’s see how this goes. For now, I’d be happy if nothing crashes in the next few days after this migration 😂


P.S.: Monitoring capabilities are also quite neat. I can monitor the performance at all times. Have a look:

Earning Money by Blogging: +1,000% Ad Income

From time to time I get to hear some criticism about having ads on my blog here. I can understand the dislike of advertising and I myself do click ads away or try to close them where ever possible and most importantly if they’re annoying. Yet at the same time, I do also have ads on my blog.

Having ads on kozen.de is in part an experiment to see myself if I can somehow be able to finance the hosting costs for this blog through such ads. Sure, I’ll have to create content that is interesting to people to come here, have a read and get some value out of it. While I believe there is an audience out there that might find my content useful, I am also sure that there is a rather large audience that finds my content not useful at all. And that is entirely fine with me.

Today when I logged onto my Google AdSense account to check on this blog’s recent performance, I noticed this little notification at the top right and after opening it, it showed me that my ad income performance went up by 1,000% per cent. Granted, I have started from low levels. This blog had not been updated for several years before I took up blogging again.

I’m not even constantly blogging right now. As you might have noticed (or not noticed :)) there are some weeks when no blog post is being published. There are just some weeks when I don’t really have a topic to talk about or when I simply don’t feel like blogging. More often though, I am just not in the mood to blog. It is a great luxury to have that choice, though.

Perhaps some day, I will be able to simply cover server hosting fees just through advertising income on this blog. Hopefully, some of my content will be valuable enough to my readers to keep coming back from time to time and be timeless enough that it is not outdated in the second it was posted here.

There’s a long way to go and blogging helps to get through that process.

Deutscher Reisepass nur noch Platz 3

Viele Jahre lang war der deutsche Reisepass das Nonplusultra der Reisepässe in der Welt, wenn es um Visa-freie Einreise in die verschiedensten Länder der Welt ging.

Seit einigen Jahren nun war der Reisepass von Singapur gleich auf mit unserem deutschen Reisepass und vor kurzem wurde Deutschland überholt. Gestern hat nun aber Japan beide überholt, Deutschland wie auch Singapur. Demzufolge ist der deutsche Reisepass auf den 3. Platz abgerutscht und Singapur wurde auch vom 1. Platz verdrängt. Die Rangfolge ist also nun folgende:

  1. Japan: 190 Länder
  2. Singapur: 189 Länder
  3. Deutschland: 188 Länder
  4. Frankreich: 188 Länder
  5. Südkorea: 188 Länder

Die komplette Liste an Reisepässen kann hier eingesehen werden: Henley Passport Index (Englisch)

Es wäre natürlich schön wieder an der Speerspitze dieser Liste zu stehen. Macht es doch unsere Reisen in der Welt so viel angenehmer, wenn man keinerlei Visa benötigt. Am tollsten fände ich, wenn wir Deutsche kein Visum mehr für China benötigen würden. Allerdings muss ich sagen, dass 188 Länder bereits so viele Teile der Welt abdeckt, dass wir uns froh schätzen können einen so weit reichend nutzvollen Reisepass zu haben.


Update 2018-10-10 9:58am: Fixed passport list index.

Makey Makey Experiments

The Makey Makey Set

Inspired by our city’s library who wants to launch a Maker Space here, I’ve ordered a Makey Makey set. Of course, the cheap version on Aliexpress rather than the original $50 one.

Makey Makey is a cool small set of cables and a circuit board. It’s basically a USB keyboard & mouse that you can control with your finger tips by closing the electrical circuit.

It is great for building small electrical controllers with it. Hand-crafted little things simply to play around and understand how things work. Silly things like a piano controlled by touching bananas for example. Check out this video on Youtube that shows what can be done: Makey Makey Examples.

So I went ahead and created myself a small little game controller. All I used was the Makey Makey set, a piece of cardboard, a bit of aluminium foil and scotch tape. It took about half an hour to craft it. Check it out:

Here are some photos of the setup from the front, back and the Makey Makey board set itself:

Stay tuned to see what other silly things we can build with that.

Bloggen oder nicht? Wer hat Angst vor den Behörden?

Bad Langensalza, dem 22. September 2018: Vor vier Monaten, also im Mai diesen Jahres, haben wir unseren Bauvertrag für unser Haus unterschrieben. Filmreif sind mittlerweile unsere weitreichenden Korrespondenzen mit allen möglichen Bau-relevanten Behörden des öffentlichen “Rechts”. (Absichtlich vage gehalten hier.) Bis heute haben wir keine Baugenehmigung geschweige denn einen möglichen Termin für den ersten Spatenstich. Viele Gründe dafür sind einem Normalbürger nur sehr schwer aber oft auch gar nicht vermittelbar.

Ich teile ja sehr gern meine Erfahrungen und würde das nun auch gern in diesem Fall tun. Jetzt frage ich mich allerdings folgendes:

(1) Ist es ggf. unklug jetzt bereits über meine Behörden-Geschichten zu bloggen?

(2) Obwohl es so in einer demokratischen Gesellschaft nicht sein sollte; Hätten Veröffentlichungen über meine behördlichen Erfahrungen ggf. Nachteile in meinen aktuell immer noch(!) laufenden Anträgen?

(3) Ist die Tatsache, dass ich mir Frage #2 überhaupt stelle, bereits Armutszeugnis für mein Vertrauen in Behörden? (Welche ja objektiv aufgrund von Sachlage entscheiden sollten.)

(4) Wenn ich jetzt nicht drüber schreibe, wann wäre denn ein “sicherer” Zeitpunkt? Nach Bauschluss, Abnahme oder vielleicht gar niemals? Würde es dann ggf. zukünftige Vorhaben gefährden?

Das war im März und sieht noch heute so aus.

FRAGE: Wie man sieht, bin ich mir nicht sicher in der Sache. Was meint ihr denn so? Rein hypothetisch gesehen.


[ENGLISH] P.S.: This post was purposely published in German. Future posts will most like be published in English again.

Spam is getting more – Why?

While back I wrote about this anti-spam plugin I’m using on kozen.de. In recent weeks the number of spam comments that plugin is flagging every day has increased dramatically. Have a look:

Spam comments flagged by Antispam Bee

I find this quite interesting and am wondering why that number goes up? Is it because my blog gets more and more indexed by search engines and therefore more spambots are finding it? For sure, the number of visits per day on kozen.de has not increased significantly.

Perhaps there are a bunch of people who don’t like what I write and they’ve submitted this site to spam databases. Yes that kind a thing exists. Or is it perhaps that the WordPress version I have installed is by a 0.0.1 version below the latest WordPress version. Thus, spam bots are finding it as an attractive target to leave their spam comments?

By the way: Most spam comments are detected as “honeypots“. So just in case one of such comments gets through: Before clicking on a link, please double-check that link in your browser’s status bar (when hovering over the link with your mouse) to ensure it’s the right destination you want to go to.


How to get a Car Insurance in Germany

To register a car – may it be a new one or one you bought second hand – you need to have at least a car insurance. Here is a quick overview of typical car insurances in Germany:

  1. Haftpflicht = Third Party Liability (mandatory)
    Like it is in many countries, it is required to have a third party liability insurance for your car in case you damage someone else’s car or hurt other persons with your car.
  2. Teilkasko = Partial Comprehensive Cover (optional)
    This optional insurance covers damages to your own vehicle to some extend. It makes sense to get this for some older vehicles that still have some decent value. For a car like ours, we did not opt for this.
  3. Vollkasko = Full Comprehensive Cover (optional)
    This optional insurance can be signed up for instead of “Teilkasko”, which covers pretty much any kind of damage or loss at your car. “Vollkasko” makes sense for brand new and high value cars.

    Have a look at Comprehensive Cover for a more detailed explanation.
Hail Damage – Typical Damage Claim for a Comprehensive Cover Insurance

Finding the Best Car Insurance

There are many ways. Most folks would just ask their favorite insurance agent, but for me, I simply went on a price comparison website called Tarifcheck.de and searched for it.

To find the car insurance of your liking you need to:

  1. Particulars of the car
  2. Particulars of the holder/owner of the car and the driver(s)
  3. Previous insurance coverage

Similarly to other countries, you’ll be classified into a “Schadenfreiheitsklasse” (SF) meaning you’ll get a “no-claims-discount” if you’ve got a good accident-free driving record. If you don’t have any record you enter the car insurance world with 100%-155% percent of the normal insurance rates. It can even go up to 245% for drivers with an extremely high record of accidents. For example, driving beginners that caused an accident themselves get put into that SF. So better drive properly and with care.

Here is a list of all such SF / no-claims-discount classes:

accident free years Third Party Liability Comprehensive Cover
SF-Class Premium in % SF-Class Premium in %
Malus Class SF M 245 SF M 160
Beginners SF 0 230 SF 0 125
Special Class SF S 155
Special Class SF 1/2 140 SF 1/2 115
1 SF 1 100 SF 1 100
2 SF 2 85 SF 2 85
3 SF 3 70 SF 3 80
4 SF 4 60 SF 4 70
5 SF 5 55 SF 5 65
6 SF 6 55 SF 6 60
7 SF 7 50 SF 7 60
8 SF 8 50 SF 8 55
9 SF 9 45 SF 9 50
10 SF 10 45 SF 10 50
11 SF 11 45 SF 11 45
12 SF 12 40 SF 12 45
13 SF 13 40 SF 13 45
14 SF 14 40 SF 14 40
15 SF 15 40 SF 15 40
16 SF 16 35 SF 16 40
17 SF 17 35 SF 17 40
18 SF 18 35 SF 18 35
19 SF 19 35 SF 19 35
20 SF 20 35 SF 20 35
21 SF 21 35 SF 21 35
22 SF 22 30 SF 22 35
23 SF 23 30 SF 23 30
24 SF 24 30 SF 24 30
25 SF 25 30 SF 25 30

So if you’re accident free driving for 22+ years, you’ll get the lowest rates available.

If you sign up for a car insurance, it appears to be rather easy to claim your previous SF with the new insurer by simply entering it and providing your insurance account number of your previous insurance. If you are coming from a foreign country, you can try to get classified into a SF class according to your no-claim-record at your insurance. However, some insurers don’t accept that. Some might give you at least a bit of a discount. So I’d recommend to give it a try and check with a few insurers on whether they can accept your claim.

We’ve signed up for a third party liability insurance that costs us €247 per year where we got classified into SF15 that gives us 40% premium we have to pay. Without such SF classification we would have paid close to €600 per year instead. So it’s worth looking into that.

On the comparison website you can also see different ratings of such insurers. They tell you how well that insurer pays back claims, how responsive they are, whether they are environmentally friendly, do everything digitally, and so on.

For a Care Free Ride

Where to Sign Up the Best Car Insurance

You can go to: Tarifcheck Car Insurance website

Simply enter your car details and personal particulars there. You’ll then get a list of insurance offers. I for my part, signed up for the car insurance right on that website. It worked quite well for me, but feel free to consult other sources too.

My decision process was very simple: I took the insurance with the best combination of claim-refund rating, customer satisfaction and of course best-price. It turned out to be a small “direct” insurance company for me. That’s fine as I expect that we won’t be needing it — hopefully.


Other articles in my German car series:

How to convert a Hong Kong Driving Licence to a German Driver’s License

It sounds easier than it is.

First off, you can drive in Germany with your foreign driver’s license for up to 6 months starting from the first day of entry. If you want to drive after that period, you’ll need to convert your foreign license to a German driver’s license.

As you know, we recently moved from Hong Kong to Germany. My wife has a Hong Kong driver’s license (even though she initial made her license in California) and we want to convert it to a German driver’s license.

My Hong Kong Driving Licence (Note: This is only valid in conjunction with my HK ID card, which is a proper photo ID. Both are linked with the unique HK ID number showing at the top right of this driving licence.)

If you have a foreign driver’s license you’ve got to distinguish between three different types:

  1. You have an EU driver’s license, or
  2. Your driver’s license was issued in a country listed in “Annex 11” of the driver’s license ordinance, or
  3. Your driver’s license was issued in another country (i.e. not listed in Annex 11 nor an EU license)

1.  Your EU Driver’s License

… is valid in the entire of European Union. Germany recognizes all EU driver’s licenses as well as the ones issue in Iceland, Norway and Liechtenstein. There is no need for converting your existing license.

2. Your Foreign Driver’s License (Annex 11)

… can be simply converted to a German driver’s license by paying a small fee (~€48) and filing a conversion form. It is recognized by Germany and your licensed driving classes get converted appropriately. This requires that your issuing country / state is listed in “Annex 11” of the “German Driver’s License Ordinance” namely: “Anhang 11” of the “Fahrerlaubnisverordnung (FeV)”.

The following countries are listed in Annex 11:

  • Andorra
  • Australia
  • Bosnia Herzigovina
  • Canada
  • French Polynesia
  • Guernsey
  • Isle of Man
  • Israel
  • Japan
  • Jersey
  • Monaco
  • Namibia
  • New Caledonia
  • New Zealand
  • Republic of Korea (South Korea)
  • San Marino
  • Serbia
  • Singapore
  • South Africa
  • Switzerland
  • Taiwan

The United States of America are not recognized as a whole. Only the following federal states are listed in Annex 11:

  • Alabama
  • Arizona
  • Arkansas
  • Colorado
  • Connecticut
  • Delaware
  • District of Columbia
  • Florida
  • Idaho
  • Illinois
  • Indiana
  • Iowa
  • Kansas
  • Kentucky
  • Louisiana
  • Maryland
  • Massachusetts
  • Michigan
  • Minnesota
  • Mississippi
  • Missouri
  • Nebraska
  • New Mexico
  • North Carolina
  • Ohio
  • Oklahoma
  • Oregon
  • Pennsylvania
  • Puerto Rico
  • South Carolina
  • South Dakota
  • Tennessee
  • Texas
  • Utah
  • Virginia
  • Washington State
  • West Virginia
  • Wisconsin
  • Wyoming

It is important to note, that not all classes of your driver’s license may be recognized. To get a clear picture of the classes you can transfer, please check the official annex 11 of FeV.

3. Your Foreign Driver’s License (NOT Annex 11)

… your driver’s license is not recognized and cannot simply converted to a German driver’s license, if your issuing country/state is not listed in annex 11 (see above point 2).

This is, unfortunately, the group my wife’s Hong Kong driver’s license falls into. After consulting with our local driver’s license government department and double-checking with them, we are now certain of the requirements to “convert” her license:

(1) Pass theoretical driving school test
(2) Pass practical driving test

Obviously, these two points are time consuming and expensive. Not to speak that if you fail one of these, you’ll have to cover repeat costs.

Costs of Tests Required

As it is in small towns, I know someone who knows someone who has a driving school. So I went on and checked with him what these tests would cost roughly.


Passing the theoretical test is not that hard. You can buy a CD and practice the multiple choice questions over and over again until you know them all. There are now even apps available that help you get ready for that test.

€35 CD
€35 Theory Test Fee (driving school – may vary)
€22.49 Dekra-Fee


It is recommended to have at least a few driving lessons to have some kind of chance to pass the practical test. Even experienced drivers might find it hard to pass this test. A small mistake and you’ve failed the test. So it was recommended to us to do perhaps 10 driving lessons to get a chance to pass the practical test.

€380 Driving Lessons (10x €38) (driving school – may vary)
€55 Driving Test (driving school – may vary)
€91.75 Dekra-Driving-Test-Fee

In total we would end up at around:

€620-800 total

This obviously depends on the actual number of driving lessons the applicant needs (if at all) and/or a test would have to be repeated, etc.

Notes on Tests in non-German: Not all testing centers seem to be offering driving school tests in other languages than German. At the DEKRA for example, I haven’t found any information for tests in English. TÜV Nord for example offers their driver’s license tests now in English, French, Greek, Italian, Polish, Portuguese, Romanian, Russian, Croatian, Spanish, Turkish and Arab.


What’s Needed For The Application of Conversion

In full, an application at the Driver’s License Department for converting a Hong Kong driver’s license or any other license that’s issued in a country not listed in annex 11:

  1. Eye Test Certificate (get at eye doctor or optometrist)
  2. First Aid Course Certificate (get at Red Cross)
  3. 1x Passport Photo
  4. Driving School Application (where you do theoretical/practical tests)
  5. Translation of Current Driver’s License

The conversion fee is €48 and can be filed before you actually do your test. From the day you pass your tests, it takes up to 14 days to issue your driver’s license.

Where to Apply for Conversion

Usually the driver’s license government department is called “Fahrerlaubnisbehörde”, which in most cases is situated at the city or county government. Larger cities have their own department, smaller ones like ours have theirs at the county’s government departments. A full list of addresses of all departments in Germany can be found here: Address Index of Driver’s License & Vehicle Government Departments (in German only)


The other way around: German to Hong Kong Driving Licence

Just FYI. A few years ago, I converted my German EU Driver’s License to a Hong Kong Driving Licence by simply filling out a form and paying a fee. In Hong Kong I did not have to do any test or provide any certificate whatsoever — except for a translated copy of my German driver’s license. It was quick, easy and straight forward.


Tid Bits:

“Driver’s license” in German is called “Fahrerlaubnis”, which is pretty much the literal translation of “driver’s license”. Colloquially it is called “Führerschein”, which is the actual “driver’s license card” you carry around.

  • driver’s license (or driving licence) = Fahrerlaubnis
  • driver’s license card = Führerschein
  • driver’s license department = Fahrerlaubnisbehörde or Führerscheinstelle
  • convert my driver’s license = meine Fahrerlaubnis umschreiben


I have written this down here in English, because many German government agencies don’t publish their information in English or in a comprehensive way. Especially for foreigners we find it being very difficult to navigate typical German bureaucracy without extensive knowledge of the German language.



Update 2018-09-20: Thanks to our very attentive reader fok, we were pointed into the right direction and corrected the actual meaning of “Fahrerlaubnis” and “Führerschein” as well as the differences between them.

Machine Learning to Stream “DeepFake” Videos in Real-Time

Machine learning is one of the major goals of the more general term of artificial intelligence. Earlier this year I read about so called “DeepFake” videos on the popular German computer science news service Heise. While the entire topic in that article is a bit sleazy, I was intrigued by the possibilities of that technology.

Basically, the “DeepFake” technology uses existing machine learning / deep learning algorithms to create models that can manipulate data in a certain quite predictable way. If you input a headshot photo of a random person, that “model” can make that person look like a very specific person. That sounds very abstract.

An example:

If I take a photo of myself, the “Nicholas Cage” model can make me look like Nicholas Cage!

In the case of those DeepFake videos, an entire video scene was processed by a certain model and basically made the actor look like a very specific different actor. So as a result, you would get a video where the actor looks very different from the one who was shot in the original film.

Real-Time is Key

For quite some years we’ve been working with streaming video for our Sky Drone products, which come in many different flavors. As a result, we have a bit of experience on how to stream video real-time. Then we thought further on how that technology of “deep faking” could work with real-time video chat. As a result, we used all the technology knowledge at hand and created a small web service that allows you to video chat with yourself. Yet, you won’t see your face, but the one of a person you choose to be. This is how it looks like:

The small website is not fancy nor is it easy to use. It just works — if you use it the right way. If you’d like to try it yourself, you can follow the instructions we posted on Reddit.

TRY HERE: Reddit – Video Live-Stream DeepFake Testing

Here is a video of a user in India who gave it a try:

How it works

You can see yourself through the webcam of your computer. That video is being streamed to a cloud computing cluster we operate. On that cluster, the “AI model” for the selected person is being applied. The resulting video is then being streamed back to your computer and shown on the screen. As a result, your face looks quite different from your actual face.

You can try to smile for example, and the model will modify the smile to a smile that celebrity would do. This includes the kind of teeth that celebrity has, the mouth and lip shape, etc.

For example, this is how it looks like when we smile while being Nicolas Cage:

Of course, a photo of a computer screen is not that nice and it does especially not show how movement in the video shows you as a “different person”. Yet, it can at least give you an idea on how that might be. Feel free to give it a try yourself.

The Future

We have some ideas on how this can be used in future – for legitimate purposes, of course. As I don’t want to spoil your thoughts … What do you think this can be used for?

Experimenting with Solar Panels

As I mentioned earlier, we are building a house in my home town Bad Langensalza. Since my teenage years I’ve been fascinated by technology of many kinds. That lead me to study computer science and later on focus my entire professional life around that. Now, building a house is – generally speaking – a rather traditional kind of engineering work. Putting up walls, a roof, do some ground, etc. We’ve found a great company to take care of all of that, but more about the house topic in later blog post.
Let me give you a little insight into my motivation on experimenting with solar panels. The house “package” we chose, came with a standard natural gas-powered heating system. That system is supported by simple solar tubes to pre-warm water. Those solar tubes don’t generate electricity, they just warm up the water. It’s basically just black tubes with water inside. We personally feel that fossil resources are generally something we should try not to use too much of. So we upgraded our “package” from the natural-gas-powered heating to an entirely electric-powered air-water-pump system. It is generally speaking quite similar to a split-type A/C that’s popular in Asia and other parts of the world. One reason for choosing that and paying for the additional costs was to allow us to eventually support our heating system with solar panels that generate electricity (see photovoltaics). Heating is in Europe what air-conditioning was in Hong Kong. It is essential for a comfortable home with Gemütlichkeit. Especially in the winter months, of course.

Before I left Hong Kong, I bought a “solar panel kit” from China and shipped it over along with my household. It consists of the following:

  1. 100W Solar Panel (monocrystalline cells)
  2. Controller unit
  3. Power inverter unit (convert DC to AC)
  4. Some cabeling

Back in Hong Kong, I already unwrapped the set to test it. You can’t be too trusty with the mainland Chinese vendors. I quickly realized that I needed a battery to get the entire thing working properly. So I decided to push that testing back to when I’m in Germany. I was quite sure my dad still had some car battery hidden in his garage somewhere. Guess what? Of course, he still had a battery!

After finally having found some time to do my experiment, I unpacked everything and set it up in their garden. I connected the solar panel to the controller. Connected the controller to the battery and connected the power inverter to the battery as well. Then I connected a consumer (a FM radio) to the power inverter to test it and switched everything “on”. Guess again: What happened?  Yep! Nothing happened. Here is how that set up looked like:

Basic solar panel setup: panel – battery – inverter – controller (left to right)

Here is a quick video about that:

Technically, it should work like this:

  1. The solar panel converts the sun’s energy into 14.4V DC electricity.
  2. The controller takes that electricity and passes it on to the 12V car battery to charge that battery.
  3. The controller ensures, the correct charge is passed. So you have to configure which type of battery you have. This depends mainly on the number of cells your battery has (e.g. 3 cells, 4 cells, 6 cells, etc).
  4. The converter simply consumes the 12V DC electricity from the battery and converts it into 240V AC electricity.
  5. Any standard consumer electric appliance can then be powered by the converter’s output (e.g. a radio).

As my radio didn’t turn on, there was apparently something wrong with my setup. So I tried several other options. The controller (the most right device in the photo above) also has two more additional outputs besides the one for the battery:

  1. A direct consumer output (voltage can be adjusted), and
  2. Two USB ports

I tried to connect the power inverter to the direct consumer output of the controller to see if my radio turns on then. Nothing happened again. Yet, the controller has a display that appears to be operating correctly. So I quickly got a USB cable and tried to charge one of my old phones through one of the USB ports. That worked flawlessly and with about ~2A output current, the phone charged up quite quickly. Have a look at the charging working properly:

Conclusion Test 1

It appeared that the solar panel worked well. The controller seems to have worked too. Also, when the battery is connected, the controller’s display output indicated that it is charging correctly. Hence, I assumed there was a problem with the inverter unit. I double-checked whether I connected the unit properly. It appeared to be getting enough electricity. That’s because the fan turns on automatically when I switch the inverter on. So it seems to be receiving enough electricity from the battery or in the other test directly from the controller. My conclusion was to try another inverter. So ordered one on Amazon.

Test 2 – New Inverter

The new inverter I ordered off Amazon cost just €20, but is also just a 300W inverter as opposed to the original inverter I got with the whole set that can do 1000W. Anyhow, I only have a 100W solar panel so far. The whole setup with the new inverter looked like this:

Setup #2: solar panel, battery, inverter, controller, radio.

Believe it or not, the setup worked out-of-the-box now. I managed to get some sound out of the radio and finally listen to the weather forecast. The lawn obviously needed some rain soon! Here is a quick video of the setup with the radio playing:

Solar Panel Photo Gallery


Upcoming Solar Panel Tests

I’m now curious on how this works with multiple solar panels and larger electricity storage. Especially, how I need to wire it to get it working properly and how much electricity it can actually collect, convert and store. Of course, there are all these theoretical calculations you can easily run based on how much a solar panel can process, what the average sunshine time is in your area, how you convert and store the electricity and so on. But all these are theoretical values and I was never a fan of plain and dry theories. I got to try it myself. See it in action and experience its practicality.

So my next solar goal is now to:

  1. Get 2 more 100W flexible monocrystalline solar panels
  2. Replace old battery with 2 new car batteries that store at least 80Ah each
  3. Install all 3 panels and 2 batteries in a more semi-permanent setting
  4. Let this run / charge / consume for a few days / weeks


The Purpose

My end goal is to cover certain roofs of our new house / property with solar panels. As we are planning to have a carport and a permanent awning for the terrace, my plan is to cover both with solar panels. Here in Germany we of course have service providers / construction companies where you can order your terrace awning or carport with a solar panel roof including the construction of such. Think: all-inclusive-service. That would be the laziest option, but also the easiest one of simply getting it done. As you can imagine, these installations are then quite expensive. I was looking at a 10m x 4m terrace awning that’s completely covered by solar panels and the price was something in the range of €35k ($41k). That is quite A LOT I find and not even close to my budget. Though, including labor I guess it may be a fair price. Yet, we still wouldn’t have a carport yet.

So, I’m experimenting with these solar panels to figure out if the solar panel part is something I could perhaps do myself. It may or may not be practical for various reasons.

  • Perhaps there’s too much work involved?
  • Perhaps the pure material costs are too high to justify their use?
  • Perhaps the efficiency of the solar panels aren’t as good on average as sellers claim them to be?
  • Perhaps my plan gets killed by special EU customs duty on Chinese solar panels?
  • Perhaps storing electricity is not efficient enough?
  • Perhaps the batteries for storing them aren’t as reliable as they should be?

There are so many questions and there are probably a lot more I haven’t even thought about yet. I won’t be able to answer at least some questions to my satisfaction, if I don’t get started. I simple need to get at least some steps closer to entirely understand the practicalities behind using solar panels. That’s what I’ll do in the next months. Let’s see how that goes.

Stay tuned for more stories on solar panel experiments and our house construction process, progress or non-progress. 


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