Solar Cooker…Patrick Sherwin and the Gosun Stove

 Solar Cooker…The GoSun Stove


GoSun successfully completed a Kickstarter campaign by raising $203,217 in late October and exceeding its own goal by more than $160,000. At only 20 minutes to a meal and safely sizzling up to 550°F, the GoSun Stove is the first practical, fuel-free cooking solution. GoSun is on a journey to revolutionize cooking both first and third worlds with their portable solar cooker.

Patrick Sherwin, GoSun founder and solar energy expert, is passionate about play, yet remains focused on solutions for our time. As a veteran solar engineer with extensive small business, international project management, and sales experience, Patrick’s love for humanity, entrepreneurial spirit, and determination drive GoSun and its solar cooker capabilities in all business facets. I interviewed Patrick and asked him the following questions:

How did the idea come to you?

I’ve been working in the solar energy field for 14 years.  11 years ago I was on a rooftop removing an old solar hot water heater. This was the first time I saw the evacuated tubes used in solar heating systems. The customer didn’t want them so I was able to take them home.  I broke them apart and started tinkering. I figured there had to be some remaining value.

So I put some hot dogs inside the glass tubes and they started frying. I built several hot dog cooker prototypes which were great for cooking hot dogs if that is what you want to do. About 4 1/2 years ago, I had an aha moment at a solar expo when I saw a 2 foot long demonstration tube on a table. I realized that this is the length I needed to make this more consumer-friendly as it could be portable and easy to use, kind of a bite size solar device.

What made you act?

When I see a good idea, I always think about how to scale it. The technology itself really pulled me in. I was intrigued by the idea of cooking with the sun at temperatures similar to a grill or stove top. This was a constant source of inspiration and it kept me tinkering.  I took a trip to Haiti and the poverty there blew me away. They prepare food indoors using wood and charcoal which affects their health and requires a lot of wood which affects their forests. Their cooking processes really stuck with me and so I created a vision for a product that could be useful in both the United States and developing countries.

I started researching the solar cooker when I got back to the US. I wasn’t able to find anything that really got the job done in a timely fashion, safely, that could handle a large volume of food, and work through a rainstorm or light wind. It was sad. In my 15 years in the green industry, I believe the cost per performance for solar hasn’t been great, but that is changing. It is hard to compete with traditional fuel sources and I am here to prove that solar is a viable option. I believe that solar will out compete traditional fuels and needs to be our primary source of power.

How was the prototype process?

I had many different prototypes. The first product used 5 1/2 foot long tubes and making a mess inside those was a real pain. When I found the two foot long tube, I was still stuck in a vertical mindset because all solar tube collectors are racked that way. The preexisting use of this technology was ingrained in me. One of the biggest design changes we made was to set it in a horizontal fashion, which gave us much more flexibility for cooking and that led to substantial design components that are integral to how our solar cooker works. This made it easier to use, to get food in and out, and to clean.

Four Years

The prototyping process took over four years and in the process I used a couple of different makerspaces. Though not an engineer, I’m an inventor born and raised, so I had to do it hands on, by trial and error. I bent all of the metal by hand because I didn’t want to spend a lot of money on plastic injection molding or CNC routing. This was before 3D printing became popular. I made all the brackets out of wood and bent metal rods. The one thing that I didn’t build myself was the glass evacuator tubes, which are made in China and part of a preexisting industry. That made the job easier as I only had to figure out how to work with the tube and how to protect it.

Developing the canoe shaped cooking tray to help move food in and out cleanly was another aha moment. It seems obvious, but it took years to develop. I used Legos, sticks, and a 3D prototype. There has been a lot of attention to detail, probing, and consideration for the user’s experience. I have friends who are industrial designers that were brought in during different stages. I’ve been involved in every stage of product design because I was so intimately involved with the details over the last 4 1/2 years. As we move into developing new products and grow, I’m trying to put more of this process on the industrial designers.

How was the patent process?

We started three years ago with a provisional patent and currently have a patent pending. A friend from high school who is an intellectual property lawyer helped me through the process. He is confident that we have a great strategy and a unique product. We’re not declaring ownership over the whole evacuated tube cooking domain, but we’re the first to do it in this way and using these components. I am confident that we will have a patent in the near future. I’m fortunate to have my friend helping me through the process so the expense has been kept to a minimum. He has a regular job but is really interested in green technology.

I’ve learned a ton during the process about technical writing and using your sensibilities to explain the device. I was really impressed with how bare bones objective the application process is. We’ve only had one office action and it’s hard to say how much of this we’ll see. At this point, everything has been planned and fairly painless. Our first patent application was rejected and we’re waiting to hear what they had to say. As far as intellectual property goes there are so many ways to look at it.  It’s very dicey when you’re filling out your comment on Kickstarter for the whole world to see. Our hope is that we build brand loyalty through great ideas, great customer service, and a quality device.

How have you marketed it?

I spend a lot of time looking at spreadsheets and market segmentation, figuring out who, what, why, where, and how to getting it in front of the customer. We’re so young that we haven’t really engaged the sales and marketing engine yet. Our Kickstarter campaign was somewhat ambiguous as to the end customer. We found that preppers or survivalists and early adopters are a big segment though we haven’t done a lot of focused or targeted marketing efforts.

What we have focused on is the name. About three years ago we chose a name only to find out a year and a half later that it had been trademarked. There was no way we could move forward so I came up with GoSun. Now we are building products under the GoSun name.  Our ethos is promoting self-sufficiency, environmentally friendly solutions, and more important to our customers a sense of freedom and enjoyment that comes with a solar cooker. You have safety and won’t have environmental issues to concern yourself with such as smoke and fire, lighter fluid, and charcoal.

The food inside the tube is being prepared in a totally new and unique way. We believe our product is for everyone. People will see solar cooking in the tube as an opportunity and not a problem. There are limitations based on size.  But once you overcome that element the options are limitless from baking, boiling, and frying. We’ve even baked bread and cookies. What is really exciting is that we are working in the developing world to get the GoSun stove in the hands of those who need it most.

What were some obstacles and how did you overcome them?

There have been quite a few obstacles.  The biggest has been what family members and friends have said regarding my working on a solar cooker. I’ve had people make fun of it and tell me that I’m wasting my time. They’ve belittled the device and the process. I would tell them about my solar cooker.  Their response would be that it’s been cloudy for a month and why am I wasting my time. That doesn’t happen anymore, now they say good job and what’s next?

What advice would you give to those interested in inventing?

I recently listened to a piece that Ira Glass was doing on This American Life and it fit perfectly. He said all artists, inventors, and makers, whether it is painting, music, software, or whatever have a certain desire for the best and a vision for what they want to create because they have good taste. When you first start making stuff, it sucks. For years it’s not going meet your standards.  It’s not going to have the feel, the sound, and the taste that you want.

You’ve just got to keep trying, keep working through it. That is the process for success. If you give up, you are 100 percent guaranteed not to get there. So my advice is: keep working at it and know that it may take years. It took years for me before I felt like I had something I could sell to another person. The problem solving, the iterations, that is so critical before you are ready to launch.

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Solar Cooker…Patrick Sherwin and the Gosun Stove

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