Blog of Urs Riggenbach

Engineering Students Complete Solar Concentrator in Pakistan

Posted Friday 31 July 2015 by Urs Riggenbach.

The engineering students at Air University completed their final project of a hybrid solar-biomass system. Their model used our Sol4 solar concentrator in combination with a biogas digester. We congratulate the students for their graduation and hope they keep pursuing the advent of renewable energies in Pakistan.

For this article the student team of Bilal Gondal, Muhammad Hassaan and Zia Bakht Butt shared with me their project report, including notes on the energy situation in Pakistan, their experience with, and the future of renewable energies. Bilal about the construction:

Your design is easy to understand and straight-forward to build. We achieved the advertised temperatures in the first try with none of the complications experienced by other students that used a different solar concentrator design.
Final moves during construction of the solar concentrator.
Solar Concentrator before mirror calibration
Solar Concentrator achieving focus point

For the students the project was an initial success. Both the solar concentrator and their biogas system managed to produce the estimated amount of energy. The students are excited about proving the baseline viability of their hybrid system.

I am sticking to the solar/ hybrid system, as it is the technology of the future. What needs to be done is to use this concept to produce energy from the small to the mega level. Industries like textiles and beverages can benefit greatly from solar/ hybrid thermal energy.
Biogas digester producing methane to heat steam boiler at night or during cloudy wheather
Solar concentrator to heat steam boiler directly during sun hours
Pakistan’s Energy Scenario [1]
- Pakistan is an oil importing country.
- Majority of Pakistan’s power generation is from furnace oil, diesel and natural gas fuels.
- Because of fast growing economy and population growth demand for energy is rapidly increasing.
- Pakistan lies in an area of one of the highest solar insulation in the world.
- The average solar radiation is 5.5 KW/ and there are more than 300 clear sunny days in a year.
- The solar potential is estimated well over 100,000 MW.

Energy Outlook in Pakistan
"Recently the idea of converting coal products into gas gained political traction in our country. Technically in this process the hard-to-reach underground coal reserves are slowly burnt with little oxygen to gradually turn the coal into flammable gas. The largest coal reserves of Pakistan exist in Thar. Now the government has resorted to produce electricity with this method.

It is hard to believe that in 2001 our country had 4,000 megawatts of excess power in our electricity grid. Today the total power supply in Pakistan has risen to 16000MW, but with population and the economy’s growth we are now facing a shortage of 4000MW resulting in power-cuts and austerity measures. This is a sad state of affairs as Pakistan has an enormous renewable energy potential, especially for solar (see box). [2]"

Solar energy is at the moment the only renewable energy source that can compete with fossil fuels and it is clean, safe and cheap energy available all over the world.

We congratulate the team to a successful build and are looking forward to see what projects the newly graduated engineering students will undertake in the future.

Solar Energy for Palestine

Posted Saturday 25 July 2015 by Urs Riggenbach.

After studying abroad and working in the solar industry in the US, Moutasem Hassan is ready to return to his conflict-ridden home country and promote solar energy for a more independent Palestine.

Moutasem is a Palestinian citizen. At age 17, he got a scholarship to attend the United World College, in India. There, among 200 students from 68 nations, Moutasem started to look for solutions that could make a difference in Palestine.

Moutasem continued his studies at the College of the Atlantic in the US and graduated as a Human Ecologist. After two years of work in the solar industry, Moutasem is ready to return home with his bold mission.

Ongoing conflict in Palestine and the Arab Spring in the surrounding countries have been a very challenging dilemma for all citizens including my family and me. Poverty and fear were the main two themes of my childhood, and are part of the Palestinian reality. I was for long time, until I left, in a broken system. I lived through the days where my father spent all his money for my brothers’ and sisters’ tuition, while the government could not pay their employees a dime.

Moutasem explains that Israel only allows few hours of electricity per day into the Gaza Strip. The high taxes the Israeli govt. puts on all imported goods constantly drive up the cost of living. Access to power and energy is a financial burden for every Palestinian citizen. These problems get even worse in refugee camps and rural areas.

The main fuel for cooking and baking is liquefied petroleum gas (LPG) that needs to be imported. Still one third of all bakeries run on wood that is slowly running out as desertification proceeds and the remaining 2% forest cover is dwindling [3] [4] [5].

It will not be an easy road to establish solar thermal energy in Palestine and my path will be filled with obstacles, but I am determined to drive this change so desperately needed by Palestine’s people.

Moutasem is motivated by the fact that solar energy not only creates jobs and reduces fossil fuel dependence, it also reduces the greenhouse gas emissions and could pose a way out of poverty. “I’m especially excited about this technology because it can be built locally, so it will not be limited by the harsh import duties imposed on us by Israel.”

As an early adopter of technology, Moutasem gets access to all construction plans and detail he needs to build his first machine in-country and demonstrate it to potential clients. This is Moutasem’s next step.

First Sizzle with the Sol4 in Switzerland

Posted Monday 20 July 2015 by Urs Riggenbach.

After setting up the solar concentrator in the school’s yard, the students had to calibrate the mirrors. Soon enough the vegetables, burgers and bacon were easily cooked with nothing more than sunlight. This is what Free The Sun is all about!

As indicated by the team it really did take us 2 hours to calibrate the mirrors but then our surprise was great once the water started boiling and the veggies and burgers started to sizzle in the pan!

Kurt Baumann, Teacher at Schulzentrum Kreuzfeld 4, Langenthal, Switzerland

It was a great success: everyone who came out of the school-building waited in line to get their share of the solar snack the students prepared for everyone.

The Next Steps

Now that the summer holidays approached the solar concentrator gets a break too, until Kurt starts the year with a new class of students. Apart from cooking and demonstrating renewable energy, schoolteacher Kurt is an artist at heart and is already thinking of using the powerful solar array for his student’s next projects.

Hybrid Power Generation at Air University, Islamabad

Posted Friday 17 July 2015 by Urs Riggenbach.

Muhammad Hassaan is a 23 year old engineering student from Pakistan. For his final project, Muhammad and his two other teammates Zia Bakht Butt and Bilal Ahmad designed a hybrid solar and biomass power generation system. Part of their system was a solar concentrator, and they were looking for a simple and effective design to bundle sunlight.

Muhammad Hassaan, engineering student at Air University.

Solar concentration and solar thermal energy are not new themes at Air University, Islamabad. Students prior to Hassaan have been experimenting with solar thermal and even attempted to build a solar concentrator.

The old model, fabricated last year based on a different design, was an 8 feet diameter parabolic concentrator. The problem with this parabolic concentrator was that it wasn’t achieving its focus point. They used small mirrors as reflecting material, almost 200 pieces of mirror were attached to this concentrator. But due to the overly complicated design and fabrication errors, the concentrator’s shape was not a perfect parabola and its focus did not gather at a single point.

With’s Sol4 model, Muhammad thinks to have found the perfect method to concentrate sunlight in an efficient and simple way. "Out of all designs that I’ve looked at, your system simply makes the most sense. "

The system is designed to be a hybrid: when the sun isn’t shining, biogas can be burnt to create heat needed to power a steam engine for electricity generation. The biogas system is designed by students Zia Bakht Butt and Bilal Ahmad, and the team is supervised by Dr. Syed Lehaz Ullah Kaka Khel from Air University, Islamabad.

Stay tuned for the next post in this sequence about spreading our technology with Free the Sun.

Swiss Schoolclass is Building a Sol4

Posted Monday 13 July 2015 by Urs Riggenbach.

Kurt Baumann is a handicraft teacher in Langenthal, Switzerland. He is our first MultiPass supporter, and wants to build a solar concentrator as an educational project together with his students.

Kurt teaches his students anything from woodworking to welding to general handicraft skills. Building the Sol4 his’ class final project and the 15 to 16 year old students are truly mastering their task.

Here are some images from the constructions underway.

Sol4 Guide Ready for Early Adopters

Posted Sunday 5 July 2015 by Urs Riggenbach.

We’ve just finished the first version of the Sol4 guide and now all our Early-Adopters get to download it and start building right away!

As early adopter you get to build first. You get access to the construction guide, and details of the expected budget, time to build and construction notes and tips. On the hub you can ask questions and provide feedback at every step. By building before we release the guides for free, you help us validate the guides and make sure that they are as intuitive as possible.

Building the Builder’s Community
Our Early Adopters are living the mission of - taking our tech to new places. In the coming weeks we’ll be posting about these builders, who they are and what they’re up to. Click here to become a builder.

Join us for the next steps to "Free The Sun"
We are continuing our campaign with the aim to provide free material for people to build their energy independence. The next milestone is the Solar Oven guide, that turns a Sol4 into an oven for baking, roasting and many other activities.

Soon we’ll also finish the first version of the Sol1 guide. The Sol1 guide will also be the guide that we release publicly first, followed by the Sol4 guide.

Make it possible, join "Free The Sun"!

Let’s build!
Urs and the team

... Read whole article

SunFire South Africa Supports the #FreeTheSun Campaign

Posted Thursday 16 April 2015 by Urs Riggenbach.

Crosby Menzies, founder of SunFire Solutions in Johannesburg, South Africa, is supporting our #FreeTheSun campaign.

It’s an important partner for us because Crosby has expertise in solar cookers and a huge network in South Africa. This team is with us since the beginning of the adventure and it’s a heart warming partnership.

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