ARTE’s ‘28 Minutes’ magazine looked at the aviation of tomorrow on Thursday 6 February. Elisabeth Quin invited @Raphaël Domjan – in his pilot’s jacket, if you please! -, to join her, with engineer Laurent Castaignède and aviation journalist Caroline Bruneau.
Perspectives, hydrogen, 100% green aircraft, airships? The discussion – and the images on the screen, including HB-SXA from SolarStratros – was… showy.
“I hope my message was clear: we need to approach the challenges of the future with optimism! If we don’t give young people prospects, we risk creating a civilisation of despair, with stagnation and the status quo. It’s not aeroplanes that need to become green, but our world and our skies”, commented the pilot of the SolarStratos mission after the programme.
Taking part in this programme was great recognition of the work being done by SolarStratos and the PlanetSolar Foundation. It was also a great way of putting the spotlight on our partners. And for solar energy!
Missed this “28 Minutes”: here it is.
Three landmark moments
The entire SolarStratos team wishes you an inspiring and fulfilling 2025! Our year promises to be high-flying… and we have at least three landmark moments in store. First, the 10,000 m record attempt, which we hope will be successful this summer over the Swiss Alps. Then, PlanetSolar Foundation’s exhibition ‘Solar Pioneers’ which will be unveiled for the first time to the German-speaking public from April to October at Primeo Energie in Basel. And finally, the PlanetSolar II expedition, which will take on new heights at nearly 4,000 m above sea level on Lake Titicaca this summer. Ready to embark on the next chapter of our solar explorations? Let’s cast off!
Full maintenance in Germany
This winter our prototype solar electric aircraft, which has notched up over 100 flights, is undergoing comprehensive maintenance in Germany. This check-up is also an opportunity to implement improvements identified after the 2024 campaign over the Alps. Next month, HB-SXA will return from its health retreat at Elektra Solar in Germany equipped with two additional half-batteries, a refined variable-pitch propeller, and an enhanced horizontal stabilizer – fully prepared for the 10,000 m record attempt in the summer.
First conference of the year
Founder and pilot of SolarStratos, Raphaël Domjan is also a renowned lecturer. He gave his first lecture of the year 2025 at ESSEC Business School in front of a thousand students. They gave him great feedback: “ Their energy, optimism and ideas gave me immense hope. It was one of the first highlights of my year. Let’s build a better future together. ”
Online competition: and the winner is…
Have you entered our ongoing online competition, available on our website ? Every year a winner receives a prize, and in 2024 that person was Daryl, who achieved several top-10 performances with a top score of 17,900 points. He wins an exclusive flight in an electric aircraft with mission pilot Raphaël Domjan. We are delighted to welcome Daryl onboard for this unique experience, combining innovation with respect for the environment. Don’t miss out – the 2025 edition of the competition is now open!
‘Solar Pioneers’ auf Deutsch bitte!
“ Die Solarpioniere ”: the PlanetSolar Foundation exhibition featuring SolarStratos, will be presented for the first time in German-speaking Switzerland from April 16 to October, at Primeo Energie in Basel. And of course, auf Deutsch bitte! The exhibition has been translated to German and features an additional module with exciting new exhibits, such as the first solar-powered FM radio and one of the first photovoltaic cells in history. So, if you’re in Basel this year drop in!
A tribute to pioneer Jacques Bonvin
The Swiss solar energy pioneer and visionary Jacques Bonvin died recently in a tragic accident. He was the very first sponsor of Raphaël Domjan and his brother Alexis. Raphaël Domjan paid tribute to the co-founder of Solstis, who had supported them early on in the SolarStratos project: “At a time when we only had ideas and dreams, he trusted us, seeing in solar energy the power of the future, long before many realised its potential,” he said. “Our heartfelt thoughts are with his family and loved ones.”
Infiltrated! An undercover spy
captures 2024 exploits on film
Have you been following our adventure this year? Did you experience the thrills and suspense alongside us from Payerne to Sion and back, in the Alpark hangars that made us so welcome, during the flights over the Alps and the great Matterhorn, soaring to 5,993 metres? Filmmaker Stéphane Chopard went undercover to capture our high-flying year, and it is a spine-tingling experience. Narrated by Raphaël Domjan this video is our Christmas gift to you, with shared hopes of reaching even greater heights in 2025. Together we aim to push the boundaries of solar energy and demonstrate its untapped potential. A decarbonized world is within reach!
Discover Stratostime 2024 here:
A visionary speaker, inspiring change
“To be a pioneer is to inspire future generations.” This quote resonated deeply with one attendee at Raphaël Domjan’s recent conference in Narbonne, France, hosted by AXA France. This video of the event captures the essence of SolarStratos’ mission and vision, and we’re delighted to share it with you:
As the founder and pilot of SolarStratos, Raphaël is not only an innovator but also an exceptional speaker. His passion and commitment to a sustainable, decarbonised world are contagious. Recently he also presented at Lakal in Saarlouis, Germany, and at the API Days Energy event in Angers, France, on December 12.
Four powerful moments from the AXA conference:
It’s winter maintenance time!
HB-SXA is on its way for a thorough winter check-up. Tucked up in its trailer, the plane is headed to Elektra Solar GmbH in Landsberg, Germany, for a full inspection that will include the engine, batteries, and more. The journey itself had its moments! The images of us crossing Lake Constance, for instance, prompted this amusing comment: “An electric, solar-powered plane… in a truck… on a boat? You SolarStratos people are mad!” Indeed, we are!
Season’s Greetings and shared hope!
As 2024 draws to a close against a backdrop of wars, uncertainty, and hesitation around urgent climate decisions, the SolarStratos team remains driven and optimistic. We are determined to seek out and promote solutions, proving through spectacular challenges that it’s possible to dream big and fly high – higher than the Matterhorn, even to the stratosphere – powered solely by solar energy. Thank you for joining us on this journey to explore new pathways toward a decarbonized and more sustainable world. We are proud to share this hope with you as we wish you a joyful holiday season and a radiant start to 2025.
Inspections, optimisations, and…
promotion
With over 100 flights completed and its biggest challenges on the horizon in 2025, HB-SXA certainly merits a thorough inspection — and that’s exactly what’s happening. At SolarStratos, hibernation never means inaction! Even when our prototype isn’t flying, the work of fine-tuning and optimising continues. Not to mention the teams ongoing efforts to communicate and promote solar energy as a key to a more sustainable, decarbonised world and cleaner skies.
SolarStratos founder and pilot, Raphaël Domjan, tirelessly channels his boundless energy into this cause that is so close to his heart. Thank you all for following our journey—your attention, feedback, and encouragement provide enormous motivation to our team!
Major winter check-up
After flying from Sion back to Payerne after the summer campaign over the Swiss Alps, HB-SXA was disassembled at the SolarStratos home base. Every part of the experimental aircraft is undergoing meticulous inspection. This winter, we will be working on integrating all possible optimisations, such as maximising the energy consumption of the batteries, to ensure we’re fully prepared for the challenges that 2025 will bring.
The first milestone of the new year will be a flight at 10,000 metres, the last step before tackling the mission’s final frontier: flying to the stratosphere powered by solar energy.
Raphaël Domjan at the forefront of raising awareness
Raphaël Domjan has had an action-packed autumn focussed on solar energy promotion. He met the public at the major Geneva event, Les Automnales, on the NaoEnergy stand—a specialist in solar panel installation, heat pumps, and solar carports, and a recent partner of the PlanetSolar Foundation, which oversees the SolarStratos mission. It was a vibrant exchange, full of energy!
Raphaël also participated in the Régionale Emmo de l’Association Progrès du Management (APM) in Lisbon, speaking at the ‘Exploration’ session alongside Laura Lange, a doctor of practical philosophy and a well-known columnist.
Breaking barriers for energy transition
On November 20, Raphaël attended a charity evening for the 101 Fund Foundation at the Cercle de l’Union Interalliée in Paris. This foundation, led by Professor Jean-Daniel Chiche, head of Intensive Care at CHUV in Lausanne, hosted an auction for which SolarStratos contributed an electric airplane flight.
Coming up next, on December 12, Raphaël travels to Angers, France, for the API Days Énergies! event. “This event is a great opportunity to share our experiences from PlanetSolar and SolarStratos to break down barriers to energy transition by exchanging ideas and solutions for a more solar-powered future,” he said.
Thank you, Bordier!
At Geneva Airport, right above the departure signage, there’s a screen nestled among the festive Christmas decorations featuring spectacular CGI footage of HB-SXA soaring above the Earth — a reminder that SolarStratos and Raphaël Domjan are preparing to reach the stratosphere powered by solar energy alone. The footage highlights solar power’s immense potential and promotes sustainability, striving for greener skies and a greener world. Our immense thanks to our partner Bordier for this incredible showcase!
Towards a solar-powered world
The figure released by the Swiss Federal Office of Energy for 2023 is striking—and exciting. New photovoltaic installations increased by 51% last year compared to 2022, reaching 1,641 megawatts by 31 December 2023. Solar panels operating in Switzerland now account for 6.4 gigawatts, supplying over 8% of the annual country’s needs. In 2024, solar energy will exceed 10% of Switzerland’s annual energy requirements, surpassing the Beznau nuclear power plant. The federal electricity law aims to increase this amount fivefold by 2034. The solar movement is in motion, and Switzerland is in the race with cutting-edge companies (see below) and centres of excellence like Neuchâtel’s CSEM leading the charge. SolarStratos aims to demonstrate the vast potential of this clean, sustainable energy source through its mission to fly to the stratosphere onboard the prototype plane, HB-SXA.
What an evening!
Titled ‘Solar in All Its Forms’, the name set the tone. On Thursday, September 26, SolarStratos and PlanetSolar Foundation hosted a gathering at the Payerne base, bringing together guests, partners, and experts to explore the latest advancements in solar energy technology. It was an inspiring evening. Many thanks to Laure-Emmanuelle Perret from LightSeeds, Pascal Rochat, Women in Power, Voltiris, Josette Fresard of Viteos, Sandra Gostanian of EXPLORiT, and all the other speakers that joined us. The event was enhanced by the poetic and musical touch of cellist Marion Devaud.
A radiant panel discussion
A highlight of the evening of September 27 was a panel discussion moderated by Alain Jeannet who led an engaging conversation with State Councilor Céline Vara, Payerne mayor Éric Küng, and Mathieu Aubert, head of the economy department for Neuchâtel canton. The future is solar, and it’s already here! “It’s a pity not all my colleagues from the Federal Assembly could attend this evening,” said Céline Vara. We’re counting on her to spread the word in Bern!
Solar and hydrogen:
The decarbonized combo
By 2026, ETH Zurich aims to meet one-fifth of the Hönggerberg campus’s winter electricity needs through solar power. This will be achieved with a pilot storage technology: excess solar electricity generated in summer will be used to produce hydrogen, which in turn will be stored and transported to a boiler. There, it will react with iron ore, producing elemental iron and water which is a storable energy source! This is truly something that will fuel the future. The Federal Council is also expected to present its hydrogen strategy for Switzerland’s energy future later this year.
Alpine views—worth the trip
Are you among those (including the entire SolarStratos team) who were captivated by the magical images of solar-powered, silent, carbon-free flight over the Alps? We never get tired of seeing them. And people keep asking for more! So be sure to check out the latest reels and souvenir photos published across our social media channels after our recent flight from Sion Airport. It was worth every moment!
Raphaël Domjan at Les Automnales in Geneva
Raphaël Domjan will be at Les Automnales fair in Geneva on Tuesday, November 12, from 16:00. As the ambassador for Naoenergy, the founder and pilot of PlanetSolar and SolarStratos will chat with guests and visitors at partner booth K28. Feel welcome to come and visit us!
Fantastic campaign above the Alps
Our Alpine summer flight campaign has come to a close without accomplishing our 10,000m objective. On September 18, SolarStratos left its summer base at Alpark, Sion Airport, to return home. Beyond the team’s inevitable frustration however, the immense amount of data and insights collected provide encouragement. HB-SXA is fully equipped to fly high, very high, and the team’s ambition of flying to the stratosphere powered solely by solar energy remains unchanged! The mission has all the tools in place to determine the best options that will make this iconic challenge a reality.
Des chiffres de cet été
The summer in numbers
Between July 18 and the return flight to Payerne, the team completed 10 flights, initially scheduled to make final adjustments, and then to attempt to reach higher than any other solar-powered plane before. Here’s the summary:
– 100th flight.
– Longest flight: 3h24m.
– Highest flight: 5,963m.
– A gallery of breathtaking photos and videos of flights over peaks, summits, and glaciers.
– Two flights over the Matterhorn, including this photo taken by Jean-Christophe Bott from the Keystone-SDA-ATS agency, and a flight over the Dent-Blanche and Verbier, where, on June 18, 2022, the first wingsuit jump from an electric and solar-powered plane was completed with Géraldine Fasnacht.
5,963 meters and then…
weather veto
On August 29, after charging its batteries to 75% and flying at over 4,000 metres, HB-SXA had to abandon the flight due to commercial aviation being rerouted through the airspace that had been reserved for SolarStratos by the Swiss Air Force. After this frustrating setback, on Friday, September 6, SolarStratos climbed smoothly to nearly 6,000 metres, its highest ever altitude. However, at 5,963 metres, high-altitude clouds and a lack of thermals put an end to the flight. After that with no favourable weather windows on the horizon and conditions quickly deteriorating to pre-winter mode with snow at mid-altitudes, it was time to head for home.
Unforgettable return flight
over the Alps
On September 18 at 16:00, HB-SXA returned to its home base in Payerne. As on the outbound journey, Raphaël Domjan flew over the Swiss Alps, sharing stunning shots of their extraordinary beauty. “We’ve learned a lot and are still as motivated as ever to go higher to demonstrate the incredible potential of solar energy in the fight against climate change,” said the pilot and founder of SolarStratos.
Thank you, Valais!
At the end of this Valais based campaign, the SolarStratos team would like to extend a big thank you to all the mission’s partners, sponsors, and friends for their trust and encouragement. Special thanks go to Sion Airport and Alpark for their warm welcome, as well as to the Swiss Air Force, Skyguide, and the Federal Office of Civil Aviation for their valuable assistance. Thank you, Valais!
ASolar power over the Alps:
A high-flying message
The SolarStratos summer show continues, oscillating between patience and impatience. We repeat to ourselves that while we all share the same desire to reach 10,000m, the final milestone before our ultimate objective of flying to the stratosphere, we must not rush. On an adventure such as ours, the stars must align before we try to reach them! On the technical side everything is in order. Our HB-SXA aircraft celebrated its 100th flight just in time for Swiss National Day – the only things that are now pending are the right weather conditions and the final administrative authorisations. Patience, patience.
On active stand-by
The whole team remains on active stand-by at our cosy VIP Alpark hangar at Sion airport, waiting for the right weather window and the necessary permits. While the famous Valaisan summer thermals have so far been slow to materialise, mainly because of the amount of snow that fell at the end of the winter at high altitude, the breathing system that our pilot Raphaël Domjan will be equipped with has now been approved by the Federal Office of Civil Aviation (FOCA). The world record attempt is taking shape, meanwhile we stand-by with our fingers crossed.
A climb high into the Swiss sky
Authorisation from the FOCA for the flight level of 25,000 feet, or around 7,600 metres, arrived shortly before the end of August. Reaching this altitude will be another historic step for HB-SXA. Until now, only Solar Impulse has flown higher using only solar energy. Test pilot Gérald Ducoin will make the flight in the next few days, as soon as a favourable weather window presents itself. Other preparatory flights carried out this month have enabled us to verify, among other things, that the HB-SXA can land with a stronger headwind. A situation that the aircraft will probably have to face when it returns to land at Sion airport after the record attempt. Yes, we are definitely ready for the world’s first attempt at 10,000m!
Flying above the five 4,000m Val d’Anniviers peaks
“What a pleasure it is to welcome you to my office up here in the skies above the Swiss Alps!” Raphaël Domjan posted two photos of his flight on 16 August, writing these powerful words: “What an incredible opportunity to greet the five 4,000 metre Val d’Anniviers peaks in Switzerland propelled solely by the power of the sun. Thank you to all those who believe in our adventure and who have supported us all these years as we work towards a low-carbon world”.
And thank you Raphaël!
Happiness… shared
Sharing the exhilaration of this period of preparation for a world first, fulfils the mission’s objective to inspire, to achieve unprecedented and spectacular performance, and to encourage people to take the plunge into solar energy and a low-carbon world. Your enjoyment of these inspiring moments of shared happiness and your reactions on social media are giving us a boost: ‘Magnifique!’, ‘Nice view!’, ‘Work like this requires a lot of patience, we wish you success!’ Thank you all very much. Keep following our flights via the virtual cockpit. And let’s get on with the adventure!
Solar flights over the Matterhorn
The SolarStratos mission has been based in the Alpark hangar in Sion, Switzerland, since the 18 July and has been flying test flight after test flight in preparation for the imminent world record attempt. Every new flight has served to confirm and optimise the parameters, and to top it all off: we have a breathtaking selection of images of Alpine scenery. “It’s fantastic to be flying on solar power alone over the Alps,” said Raphaël Domjan. And returning to the landing strip while continuing to charge the batteries breathes new life into the mission’s message of harnessing the formidable potential of solar energy for a low-carbon, more sustainable world where we can continue to dream and to fly. High up. Hang on tight!
A stunning transfer flight
It had to be postponed twice, but on the 18 July, on our third attempt, we got lucky and HB-SXA piloted by Raphaël Domjan took off from Payerne, destination Sion via the Col de Sanetsch. The plane was welcomed to the Valais airport by a group of media who captured the beautiful landing live. To watch it again, please click here. Raphaël Domjan was also a guest on Channel 9.
The Matterhorn and Mont Fort really suit her!
On the 19 July, the day after arriving in Sion, HB-SXA took a trip to the Matterhorn. The resulting images of SolarStratos flying past this extraordinary landmark are powerful and highly symbolic. On the 26 July, Raphaël Domjan set course for Verbier, Mont Fort and Pierre Avoi to ride the thermals. He flew for an hour and forty minutes up to an altitude of 3,970m, and once again we were rewarded with some exhilarating images of the solar-powered flight!
The record attempt has caught media attention
Preparations for the altitude record attempt have caught the attention also of the German-language media in Switzerland with reports in the Aargauer Zeitung, the Bieler Zeitung and the Sankt-Galler Tagblatt. 20 Minuten in particular have reported on the challenges and the risks involved in the imminent record attempt. Please click here to watch the SwissInfo video. Agence France Presse (AFP) was also present in Sion, and the report was picked up by La Presse.
Such suspense!
To test the aircraft in the thermals, you must first find them. SolarStratos has enlisted the help of forecasting engineer and experienced glider pilot, Aude Untersee and the assistance of a reconnaissance motor glider to find the updrafts that form in summertime. The best way to maximise on them in terms of altitude, range, and engine power required, was refined and the team carried out a new flight around the Matterhorn passing from one thermal to another on the 30 July.
The team is continuing to work on preparing the aircraft and obtaining all the safety guarantees required for this very high-altitude flight.
So much suspense!
Since 18 July, our solar-powered electric aircraft has been based at Sion Airport, in preparation for this summer’s world premiere attempt at 10,000 metres over the Alps.
After this transfer flight from Payerne, HB-SXA has already flown over the Matterhorn, then Verbier and Mont Fort in particular, to check the plane’s performance in thermals. These development flights in preparation for the imminent altitude record attempt are continuing. Follow us and experience these sorties with us via our virtual cockpit and on our social networks. It’s exhilarating! You can relive the Payerne-Sion flight over the Col de Sanetsch here. Many thanks to Sion Airport and Alpark for their warm welcome, and a sunny summer to all.
HB-SXA to head to Sion to take up residence
“This time, the real adventure begins”. Both Raphaël Domjan and Roland Loos, respectively pilot and CEO of the mission, have spoken the exact same words on two different occasions. And as summer 2024 heats up, the moment for HB-SXA to take up residence in Sion approaches. This will be a key moment in the SolarStratos mission.
From mid-July, the SolarStratos team will be based at the Valais airport to launch a new altitude record attempt for a manned solar-powered electric aircraft to fly at 10,000 metres or more, marking a new milestone on the journey to the stratosphere. Once the plane is on the tarmac in Sion, and the final tests have been carried out, particularly in thermal winds, the team will go on standby for the right weather window.
Stay tuned if you want to spend the summer flying over the Alps: you can put yourself in the driving seat via our virtual cockpit.
A postponement…
Despite seemingly favourable weather conditions on the ground, the flight from Payerne to Sion scheduled for the 17 and then the 18 June had to be postponed. The wind and turbulence over the Sanetsch Pass were too strong to risk it. Our thanks to the media who were waiting for us in Sion for their patience. Some of them, such as Rhône FM, didn’t miss an opportunity to interview Raphaël Domjan about the relocation and the upcoming record attempt.
Already very high – above his hometown!
One of Raphaël Domjan’s recent flights this month saw him soaring at almost 4,000 metres over his native Neuchâtel. He shared his excitement at realising a dream, which sees “innovation and technology working together to preserve our planet”. The SolarStratos pilot took the opportunity to thank all those who are making this adventure possible by sharing his pioneering and exploratory spirit. “Let’s keep aiming for the stars, fuelled by the inexhaustible energy of our dreams, the sun and our thirst for exploration”. Beautifully put.
SolarStratos shines in France
SolarStratos is causing a stir among the French media. The imminent altitude record attempt has been announced by several French TV channels and newspapers. Raphaël Domjan appeared on the set of France 5’s “C à vous vous”, just after Prime Minister Gabriel Attal, with whom he exchanged a handshake and a few words before inviting the politician to come and fly with him one day. France Inter and the major daily Le Parisien have also highlighted the challenge scheduled for July 2024. In Switzerland, l’Agefi’s Be to B programme is also covering our adventure.
A breath of fresh air in freefall!
Flying at high altitudes where oxygen is scarce requires special measures and safety precautions. On 12 June, Raphaël Domjan tested his complete oxygen system in freefall, in case he ever has to eject from HB-SXA. He completed three jumps from an altitude of 3,000m accompanied by his trainer Geraldine Fassnacht, and everything went perfectly. The tests produced some stunning shots which we’d like to share with you!
A first-rate team
The traditional SolarStratos team photo was taken by Fred Merz on 17 June. Our photographer wanted to highlight the members of the mission in the foreground, and you can see them united around a shared passion: the HB-SXA at its home base in Payerne. Next stop: Sion. Onwards and upwards!
