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Meet the Inventor of the Solar-Kettle Thermos Flask

Alex Kee, Akayconsult, The Scientific Student, SK-TF, Solar-Kettle Thermos Flask


Alex Kee is the inventor, designer, and contact point for the Solar-Kettle Thermos Flask (SK-TF), a portable solar cooking device that is capable of sterilizing water and other materials. I had the pleasure of interviewing him over Skype. He was initially drawn to designing the SK-TF because he wished to deliver clean drinking water to developing countries whose only plentiful, obtainable resource is sunlight [1]. The organization he founded, AkayConsult, is a non-profit based in Malaysia focused on helping to provide solar cooker devices to regions that have inadequate access to safe water and sanitation [2]. He says that “in resource poor areas, sunlight is more accessible than materials such as chemicals that might otherwise render water potable” [1]. By utilizing the SK-TF to harness energy from the sun in order to heat water for 6-7 minutes at a minimum temperature of 65ºC (solar water pasteurization), Kee states that the water can be made safe to drink [1]. The SK-TF is a device that helps open the possibilities to helping provide long-term access to potable water to developing nations around the world. It is reusable and simple to utilize, with no replacement parts needed over time.  Kee himself has been using a single SK-TF in his own daily life for 12 years!

Kee has championed the device by appearing in interviews, as well as attending the International Solar Cookers Conference in Granada, Spain in 2006 to help publicize the SK-TF [2].  The device has been in commercial production and sales since 2003 [3]. Since working on the SK-TF project, Kee has also developed a larger version of the SK-TF, the Solar Vacuum Tube Oven (SaVeTaO,) which is currently in commercial production and sales.

The Scientific Student, Solar-Kettle Thermos Flask, Alex Kee, Solar, sun


The Problem

The WHO/UNICEF Joint Monitoring Programme (JMP) for Water Supply and Sanitation estimates that in 2015, 663 million people still do not have access to improved drinking water sources [4]. Water that is not deemed as safe runs the possibility of containing contaminants such as fecal matter and garbage, which can promote the spread of pathogenic microbes. These microbes are associated with diseases that cause diarrhea, and result in the death of approximately 1.5 million people each year [5]. Most diarrheal related deaths occur in developing countries due to higher proportions of unsafe water, poor sanitation, and inadequate hygiene [6]. With unsafe water, an effective, recommended method of destroying pathogens is to boil the water for at least 6 minutes [7]. Downsides to boiling are the large time and fuel requirements that the process can entail, which can make it difficult to carry out in poorer regions of the world.


How does the SK-TF work?

The Solar Kettle-Thermos Flask (SK-TF), as reported by AkayConsult, provides a cost and time efficient means by which users can effectively boil and make their water safe through the utilization of an easily accessible resource: sunlight. The SK-TF employs a unique vacuum tube design to capture and store solar energy from the sun [8]. This energy can then be converted to thermal energy to heat the internal environment of the flask and boil the water within [9]. The tube is composed of an inner glass layer with a dark exterior of selective coatings that heats up in sunlight, and an outer transparent layer that allows the light to enter [10]. The space between these two glass layers is devoid or mostly devoid of air, creating an insulating vacuum that traps heat and ensures the water will be pasteurized and remain hot [8]. In order to set up the SK-TF, the tube can just be simply placed in the Sun, although the optimum set up is to angle it perpendicular to the elevation of the Sun, with the bottom part of the tube pointing towards the Equator. The device can then be filled with water, closed with a cork like stopper, and left unattended [9]. The SK-TF (as reported by AkayConsult), if empty, reaches temperatures of more than 200 ºC within 1 to 3 hours, and can therefore have multipurpose uses not only as a water boiler, but also as an autoclave to sterilize equipment, as well as a cooking oven for food that will fit into the cavity of the flask [10].

The Scientific Student, SK-TF, Solar Kettle Thermos Flask


In order to purchase the SK-TF, or make further inquiries about the device, please contact Akayconsult at or

Editor: Shreya Singireddy


  1. A. Kee, ‘Interviewing Alex Kee – Solar Kettle-Thermos Flask,’ (October 28, 2015.)
  2. Solar Cooking, ‘Alex Kee’, 2015. [Online]. Available:
  3. World Health Organization, “Compendium of new and emerging health technologies,” World Health Organization, Geneva, 2011.
  4. World Health Organization and UNICEF, “Progress on Sanitation and Drinking Water: 2015 Update and MDG Assessment,” WHO/UNICEF Joint Monitoring Programme for Water Supply and Sanitation, New York, 2015.
  5. A. Prüss-Üstün, R. Bos, F. Gore, J. Bartram “Safer water, better health: costs, benefits and sustainability of interventions to protect and promote health,” World Health Organization, Geneva, 2008.
  6., ‘CDC – Global Sanitation and Hygiene Related Diseases and Contaminants – Healthy Water’, 2015. [Online]. Available:
  7., ‘WHO | Emergency treatment of drinking water at point-of-use’, 2015. [Online]. Available:
  8.  A. Kee, ‘Technical Data of Solar Device’.
  9.  Solar Cooking, ‘Solar Kettle-Thermos Flask’, 2015. [Online]. Available:
  10.  A. Kee Koo Yak, Proceedings of ISES World Congress 2007 [Vol. I – Vol. V] Solar Energy and Human Settlement. Springer Berlin Heidelberg, 2009, pp. 1939-1946.