Q51 – Why don’t we all use Solar Energy?


We want to show our population that solar energy is our future.

Where are the advantages or disadvantages? What do you need for building a solar construction? Will the usage of solar energy increase in the future?

Solar energy is certainly a very interesting regenerative form of energy. The most important advantage for us is that solar energy is renewable. Nowadays, we should avoid using nuclear energy and rather improve in renewable energy sources. Our ecological attitude has to increase. If you want to build solar collectors or something similar, you get a contribution from the “Elektrizitätswerke” of canton Zurich (EKZ) per m2 collector area. The only condition is that you need a minimal surface of solar collectors. A little disadvantage is that solar energy is still more expensive than a normal heating installation with fossil fuels.

In conclusion, there are definitely several disadvantages (e. g. expensive original costs) but, on the other hand, we have strong arguments which speak for a usage of solar energy. Furthermore, we want you to remember that we only have one world and we should take care of it.

Advantages Disadvantages
+ Free of charge Expensive production of the collectors (there are also used toxic materials !)
+ Unlimited available Unsteadiness of solar radiation
+ Clean source, no exhaust Huge demand for space
+ Independence from the electric power station Expensive original costs

Interview mit dem Besitzer einer thermischen Solaranlage, inkl. Wärmepumpe
Vor- und Nachteile der Sonnenenergie, Solarwärme (swissolar.ch)

Q51 - Why don't we all use Solar Energy?

Development of solar energy production

Since the early nineties energy which is gained by solar energy has improved a lot. This improvement is the effect of experiences which people made with for example nuclear energy. The Swiss nation were sensitized about this issue during the last. The graphic shows us that in Switzerland the biggest energy yield is originated from the photovoltaics collectors. A possible reason for an improvement since 2011 is because of the incidents of the nuclear accident in Japan (Fukushima) in March 2011.

Table (1) In a first step we transformed MWh to KWh
Table (2) Afterwards, we wanted to know how many flats can be provided with solar energy per year (five-room- flat with stove and tumble dryer, without an electric water heater): 4’500 kWh/Jahr, Kategorie H4).

Energy output: 1990 2007 2014
Glazed collectors 14‘900 MWh 14900000 KWh 191‘690 MWh 191690000 KWh 549‘240 MWh 549240000 KWh
Unglazed collectors 14‘420 MWh 14420000 KWh 549‘240 MWh 549240000 KWh 65‘090 MWh 65090000 KWh
Photovoltaics 1‘450 MWh 1450000 KWh 28‘550 MWh 28550000 KWh 841‘570 MWh 841570000 KWh
Energy output: 1990 2007 2014
Glazed collectors 14‘900‘000 KWh 3‘311 Whg. 19‘169‘0000 KWh 4‘260 Whg. 549‘240‘000 KWh 122‘053 Whg.
Unglazed collectors 14‘420‘000 KWh 3‘204 Whg. 549‘240‘000 KWh 12‘205 Whg. 65‘090‘000 KWh 14‘464 Whg.
Photovoltaics 1‘450‘000 KWh 3322 Whg. 28‘550‘000 KWh 6‘344 Whg. 841‘570‘000 KWh 187‘015 Whg.
Whg. = Wohnungen (habitations)

Our expectation for the future

In the next few years the usage of solar energy, or in general, renewable energy sources will increase because of the fear of accidents such as in Japan 2011. Furthermore, we think that our government will raise the support for solar energy. The population is getting more and more aware of and sensitized with the issue of non-renewable energy.


Verglaste Kollektoren (glazed collectors) – Verglaste Flachkollektoren werden idealerweise für Anwendungen im Temperaturbereich zwischen 30°C und 60°C eingesetzt. Sie eignen sich hauptsächlich zur Wassererwärmung und zur Heizungsunterstützung. Diese Kollektoren können in Schrägdächern und Fassaden integriert oder auf Flachdächern und am Boden aufgeständert werden. Die Lebensdauer beträgt rund 25 Jahre.

Unverglaste Kollektoren (unglazed collectors) – Der Einsatz unverglaster Kollektoren beschränkt sich auf Niedertemperaturanwendungen wie die Schwimmbad- Wassererwärmung oder die Warmwasser-Vorwärmung. Idealer Einsatzbereich sind Anwendungen, die maximal 10°C bis 20°C über der Aussentemperatur liegen. Da Verglasung und Wärmedämmung fehlen, ist der Wärmeverlust bei Anwendungen mit höheren Temperaturen zu gross und der Nutzungsgrad zu gering. Die meisten unverglasten Kollektoren bestehen aus Kunststoff. Die Aufstellung erfolgt auf Flach- oder Schrägdächern. Ein Windschutz erhöht den Wirkungsgrad. Die Lebensdauer liegt bei 30 Jahren.

Photovoltaik (photovoltaics) – Unter Photovoltaik versteht man die direkte Umwandlung von Solarenergie in Elektrizität (siehe auch Q61 – Photovoltaic Cells)

Markterhebung Sonnenenergie 2014 (swissolar.ch)

Wieviel Strom verbraucht ein durchschnittlicher Haushalt? (groupe-e.ch)

It is very impressive to see that Germany is the pioneer in producing solar energy. On the other hand, it is a bit frustrating that the US, which has a large area of landscape, isn’t very innovative with investing in renewable energy sources. Also Australia, where there is a lot of sun, isn’t on the peak of producing solar energy. There is still a great potential for improvement.

Europa hat die meisten Solaranlagen – „Groß-China“ produziert sie (oiger.de)

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Interview mit dem Besitzer einer thermischen Solaranlage, inkl. Wärmepumpe

  1. Wie kam es zu dem Entschluss, bei erneuerbaren Energien sich speziell für Solarenergie zu entscheiden?

Ich habe ökologisch und nicht ökonomisch gedacht. Der Gedanke an die Umwelt stand für mich und meine Entscheidung im Vordergrund.

  1. Wie sieht die Unterstützung (z.B. finanziell, durch den Bund) aus?

Man wird von der EKZ unterstützt. Man erhält einen Sockelbeitrag pro Quadratmeter Kollektorfläche.

  1. In welcher Zeitspanne „amortisiert” sich eine Solaranlage?

Die Amortisation war eher zweitrangig, da primär der ökologische Gedanke im Vordergrund stand. Die Amortisation hängt ebenfalls von der Primärenergie ab.

  1. Wie steht es um den finanziellen Aufwand zur Errichtung einer Solaranlage?

Die Errichtung einer Solaranlage ist finanziell aufwändiger als bei einer herkömmlichen Heizung mit fossilen Brennstoffen.

  1. Vergleicht man den Wirkungsgrad einer Solaranlage mit einer herkömmlichen Heizung; was lohnt sich mehr?

Solar speichert die Wärme mit technischen Wärmespeichern um sonnenarme Zeiten zu kompensieren und auch zu überbrücken. Somit hat man durchgehend die gleiche Leistung.

  1. Was waren Hürden/Hindernisse auf dem Weg zur Solaranlage? (Erfahrungswert)

Bei der Realisation der Erstellung von Solarkollektoren gab es eigentlich kein Problem. Lediglich die EKZ hat eine Auflage betreffend der Kollektorfläche gestellt.

  1. Wird das Erstellen von Solaranlagen in der Schweiz in der Zukunft zunehmen?

Ja, denn man möchte in Zukunft eher von Atomenergie wegkommen und auch die Fossilenergien werden weniger benützt. Der Klimawandel ist der Bevölkerung je länger je mehr bewusst und man wird zum Wechsel gezwungen.


created by:
Sina & Linus, VZA

7 thoughts on “Q51 – Why don’t we all use Solar Energy?

  1. Dear colleagues

    Your project took my attention first because of the bright shining headpicture, so my first impression: interested..

    I could easily read through everything, it is well-structured and I specially liked the vocab in which you explained the foreign words for our german speaking visitors. Also the chart with the advantages and disadvantages is pretty creative.

    As you may know, we did our project about the solar energy aswell, but more specialised into the photovoltaik cells,
    so I allow myself to say that I maybe got some more knowledge in the topic as others do.
    And I would say you did a really great job and can stand by every information you transmitted in your examples,
    to improve in the future I can mention something very superficial about the chart with of the development of the solar energy production where you used the KWh and MWh, nice idea but it took me a while to understand it. But as I said, really just a superficial cirticism, great at all though!

    Kind regards
    Loris Fortino, VZB
    Team Q61 Photovoltaic Cells

  2. Dear solar energy group

    First things first, you catched my attention with your very clever structured project report. So I kept on reading. I didn’t know that we have the possibility to gain that much heat and energy only out of sunlight. I also appreciate the vocabulary, it helped me a lot to understand the relations in your project. Another point I want to
    highlight is your clear sctructured chart about the advantages/disadvantages.

    One last point I want to mention additionally, is that I do not exactly know how solar cells work. Maybe you could explain that with a video for example.

    All in all a great project!

  3. Dear Team Q51

    That is a interesting topic you have chosen. I also thought that solar energy might be our futur, but I never was aware of the real advantages and disadvantages. Thanks to your project this has changed now.

    You can find all the important informations here and it is also very well structured. The high cost is the biggest disadvantage for me. I hope that there will be a cheaper solution soon. That would be a reason for me to switch to solar energy.

    Best regards from Lucien VZA

  4. Dear Solar Energy Group

    I really appreciate how well structured your project is. It is very easy to read and understand and you lead the reader to the important points.
    Furthermore, you did an interesting and informative inteview with good questions and answers and the chart is very useful to compare the different energy consumption types. I would only add a few pitcures, perhaps to illustrate how solar cells work.

  5. Dear Team Q51

    I think your project includes a very important issue which you explained in a interesting way. Your contribution is well structured and I like that you did an interview. But for me it is not clear yet with whom exactly you have done the interview.

    How about a list of things which can be turned on by Solar Energy. That would be interesting as well and would maby an improvement for your contribution but thats just an idea. I found a link which mention some ideas: http://www.globalsources.com/ST/12-Average-Things-Solar-Makes-Cool.html

    Overall you did a very good job and I am looking forward to more pictures 🙂

    Sarah Keller, VZB

  6. Dear Solar-Energy-Group

    You have done an excellent work; the interview, the chart with the kWh and all the other information. Your small chart about the advantages and disadvantages of using solar energy is a really good way to illustrate them to people who have never heard of it.
    I would have found it interesting why lots of people don’t make any usage of this renewable energy – I mean of course it costs a lot more – but maybe with a survey you could have really digged deeper into the reason why. Have they never heard of it? Are they too lazy? Who knows 🙂
    Maximiliane Egli VZ B

  7. Hello solar-group. Your project is very good structured. What I like most is that you named positive and negative aspects of solar energy, if i’m honest, i really did not know, that there are also some negative aspects of it. At the same time I’m very happy about your interview. It is very interesting and it links your project to the reality, so it is easier to understand.
    The following link could maybe help people to understand some difficult points better: https://m.youtube.com/watch?v=ZFlG4bz0Cfg

    Because of the fact, that I love pictures inbetween of texts, I would suggest to add one more next time. At least, this is the only point which i would improve.

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