Friday, November 14, 2014

Gonzo on the pan!

Our green team set out to see if solar power can be a practical way to power a vehicle...
The challenge we set ourselves was to see how well a vehicle could perform powered by 1000W of standard commercially available PV panels. The vehicle was to have no battery storage at all.
The result was the strange device you see below. The vehicle is aptly named "Gonzo"!
To test how fast Gonzo really can go we went to the SA capital of speed namely Verneukpan in the Northern Cape. Gonzo managed 37,1km/h. With some improvements we plan to return soon with our eyes firmly on one or more solar speed records that look to be do-able.

Here are a few clips of Gonzo in action

Wednesday, May 28, 2014


The NMMU's centre for energy research (CER) has for a few years been feeding electricity into the grid from solar panels. Yesterday however marked another first as an NMMU wind turbine was "grid tied". The unit produces up to 2.8kW and incorporates a wireless data link. Once data is available on the performance of the turbine we will post it here.

Monday, May 5, 2014

Twerly - coming to a lamp pole near you soon!

NMMU's Twerlys about to make history.
Watch this space.
Well done to the entire Twerly team!

Saturday, April 5, 2014

Solar water pumping

Solar water pumping has been used for a number of years around the world. Typically it involves a few PV panels and a small DC low voltage pump directly connected. Water flow is normally not spectacular and the low voltage requires thick expensive cables.
Enter 3 Phase AC high voltage systems which are suddenly seeing a lot of attention........
The video shows an "UBER" pumping system we are playing with at the moment. 400V of DC from 2.3kW of PV driving a 2kW submersible pump via a 3 phase inverter/controller.
Performance is really impressive with about 16000 litres per hour (at zero head). We predict 11000 litres per hour at 20m head. The system is scale-able and could easily be sized up to run large centre pivot irrigation systems. In our case we are going to use it for a pumped hydro storage experiment amongst others.

Picture below shows the 2.3kW PV array ready for action!

Wednesday, March 5, 2014

Front cover of the vision 2020 booklet

Look at those wind turbines....exciting "green" times ahead!!!
It is refreshing to be part of an organization that understands the importance of going green.

Friday, February 28, 2014

Flat concentrating reflector

Sean Poole CAD designed this concentrator and 3D printed it. He then stuck on all the little pieces of reflective material. It has a very small focal area thanks to the accuracy of the 3D printing. Might make a neat reflector for a solar cooker?

Saturday, December 21, 2013

Solar cooker mark 7

As with most good ideas there exists a large chasm between prototype#1 and a final, practical, useful device. This was certainly the case with the solar cooker. After much brainstorming and many experimental prototypes I now have a workable device. The trick is to keep the pot at the focal point at all sun angles and to keep the pot stable and level. Mark 7 has now cooked a number of meals and boiled many kettles of water. The performance far exceeds my expectations and has very similar cooking power to a typical gas stove burner. This is now truly a useful alternative to a conventional stove or kettle. Now to figure out a way of getting one into every household in Africa....


Tuesday, November 26, 2013

Tax break for greenies

Tax Alert
22 November 2013
Energy Efficiency Savings Incentive comes into operation
Section 12L of the Income Tax Act (ITA) provides for a tax allowance for energy efficiency savings. It was originally inserted in 2009 and substituted in 2012, but remained ineffective until a notice bringing it into effect was published and the accompanying regulations issued, both which have now been done.
As part of Government’s efforts to promote energy efficiency savings, section 12L of the ITA was inserted to provide an income tax deduction to qualifying taxpayers. This tax incentive provides for an income tax deduction equal to 45c for each kilowatt hour (or equivalent) saved by the taxpayer during the relevant year of assessment against a baseline from the beginning of the year.

In order to obtain the deduction, a taxpayer must register with the South African National Energy Development Institute (SANEDI), appoint a measurement and verification professional to report the energy efficiency savings, submit the report to SANEDI and submit the certificate issued by SANEDI to SARS with the claim of the deduction.

On 8 November 2013 the Minister of Finance issued a notice that section 12L came into operation on 1 November 2013. It is not entirely clear, but presumably the deduction will be available for years of assessment ending on or after that date.

Monday, November 11, 2013

Solar cooker

In a sun drenched continent like Africa, solar cooking really does offer a viable alternative to traditional methods. Our simple fiberglass parabola lined with inexpensive reflective vinyl provides roughly 1 kW of heat. The kettle containing 2 cups of water is brought to the boil in less than 3 minutes! It seems so simple what's the catch.......well we can't find one so far! Looking on are Sean Poole and Mohaman Maidadi.

Tuesday, October 22, 2013

Metrowind wind farm

Congratulations to Metrowind on the successful lift of their ninth and final rotor this morning.
Truly an impressive site to have witnessed! Over 70 tons to a height in excess of 100m. The crane used is the biggest in Africa at present. The Eastern Cape seems to be fast turning into the "Green Capital" of SA!

Monday, October 14, 2013


Report by Sean Poole
A new e-bike! This is the first step in our new project for creating a renewable energy transport system, which will hopefully eventually be implemented at NMMU and provide transport for students and staff. This system will allow students/staff to logout an e-bike with their card and then log the bike in later at any other docking station at any campus. These docking stations will charge the batteries of the bikes using renewable energy sources such as wind and solar energy.

This first bike will be used to measure power consumptions and practicality. Here is my 10 cents worth about the e-bike (after about 300km on the clock).

·         So far the electricity costs riding to work and back are about 2 cents per km (yes that’s 50km for every R1 of electricity)

·         I complete the 20km round route to work and back wearing exactly what I would wear at work (long pants and maybe a warm top) and arrive at work fresh without sweating.

·         Many comments that I have received are that an e-bike is a ‘lazy man’s bike’. I would have to completely disagree. An e-bike is not a form of exercise (for obvious reasons) but rather and alternative form of transport to taxis, cars, motor bikes, etc. And so, by using an e-bike as an alternative transportation I not only save on costs and limit my impact on the environment, but I also exercise more than I would have and have a better lifestyle.

·         It takes me less than 25 min (my record is about 21 min) to complete the 10km route to work in the mornings, which when compared to the 15-20 min it takes in a car, makes an attractive alternative.

In conclusion I am really enjoying the use of the e-bike and (as long as the weather is good) I will continue using it to get to work and back. 

Tuesday, August 27, 2013


Apparently the first commercial wind turbine in SA??

Friday, June 21, 2013

Weekend Post 15 June 2013

We're in the newspaper!!
Well done to Sean and Mo and to all the other "green team" members who made these and all the other projects happen. The group is gathering momentum and exciting times lie ahead. The green energy boom that we are entering is creating wonderful opportunities for us to apply our minds and have fun whilst solving issues that effect our fragile planet.

Friday, November 9, 2012

Riaan Opperman's green masters

Riaan is progressing well with his Master's project which has involved building, refining and quantifying the workings of a spiral pump. Little theory exists on these ingenious positive displacement pumps and Riaan hopes to give the end user of such a device helpful tools to assist in optimising the pump for each particular application. Powered only by the river flow, Riaan's spiral pump shows promise as a means of getting water from the river to where it is needed without burning precious fossil fuel!! Apart from the obvious application in farming it would also seem ideal for households located close to a flowing river. Riaan has gathered most of his data and is now processing this and putting pen to paper with a view to graduating in 2013.

Lots more pictures and clips at

Thursday, November 8, 2012

Domestic scale CSP with rock storage

One of the "green" team's latest projects is to heat air using parabolic troughs and then use it to heat rocks stored inside a vacuum insulated chamber. The idea is to then use the heat later when you need it. We are hoping to achieve rock temperatures of around 300C and retain the heat for 2 to 3 days. The heat can be used for water heating or even for factory process heat if we scale up the size of the system.

Thursday, August 4, 2011

"Off the grid" using solar

South Africa is a sun drenched country.
Electricity is becoming expensive.
Solar panels are becoming cheaper.

Is it viable to run your home off solar power?

Watch this blog to find out!!!

The pics show an installation at a Port Elizabeth home.

9 months have elapsed since the posting above. The system generates about 5kW.hrs per day. This is adequate to run all the household lighting as well as one plug circuit which carries critical items such as security, automated gate etc. The household demand is about 20kW.hrs per day. If the number of solar panels can be increased fourfold the house can run entirely independently of the grid. The lead acid batteries, MPPT and inverter have worked perfectly so far. Is it viable? Not from a purely financial perspective BUT the convenience of having power during power interruptions is priceless, as is the knowledge that some of the power in the house is sourced from somewhere other than a coal fired power station!
Will it become financially viable? In my opinion YES in the near future. PV panels are available at approximately half of the price I paid...and they are getting cheaper daily. The other elctronics are also being manufactured in higher volumes locally than before and are becoming cheaper. The batteries remain a problem. I sourced a hand picked set of second hand batteries which I pamper. So far they have worked very well and cost about a quarter of the new price.
Bottom line........It's not the cheapest alternative or the easiest BUT it is likely to be the only sustainable way to power our houses into the future!!

Monday, July 18, 2011

Mgcawezulu school project

NMMUGREEN are proud to have been able to asssist the "Touch Africa" charity organisation with this project. Touch Africa support a number of rural schools in the former Transkei. This particular project involved giving the school a wind energy derived power supply capable of running one light in each classroom and one TV set. The turbine chosen was a helical savonius (developed at NMMU). The reason for choosing this type of turbine was primarily due to the low capital cost (can operate without a control system).
The turbine was lifted into position yesterday with the school children watching. All the kids were neatly dressed in school uniform and very excited (on a sunday in school holidays!). As the power was turned on they all crowded into a classroom to watch TV and were never seen again!

In a light wind yesterday the turbine was charging the 12V battery bank at between 3 and 6 amps and the usage was 9 amps. Considering the good position of the turbine (9m high on an unobstructed hill) it looks as though the turbine will be able to satisfy the school's needs. This project is a pilot and if successful Touch Africa plan to replicate it at other schools in the area.

Monday, May 30, 2011


NMMUGREEN has received a massive boost with the donation of:
a) Twelve 640Ah 2V batteries - from Powertech (Willard)
b) A KESTREL 1kW pitch controlled wind turbine - from Kestrel (Eveready)
c) A 60A wind turbine controller (MPPT) - from J&J electronics

The system is currently being installed and should be up and running within 2 weeks. This system represents the "state of the art" in domestic sized wind energy generation and storage. Furthermore these products are all local and demonstrate that South Africa and in fact the EC are leaders in this field.

In addition to the solar and wind systems already running on the NMMUGREEN rooftop we will now be generating (and storing) enough power to run the entire Siemens laboratory and more. More importantly we will be showcasing these fine products in action and thus making learners and the public aware of this vital technology.

More good news is that the green energy web portal is almost ready to go live. Live data is already available on a PC screen in E22. More details soon....


Monday, May 23, 2011

Green Transportation

There are ways of getting between A and B that use less fuel and save time in comparison to motor cars....
Yesterday a Whisper Motorglider aircraft flew from Windhoek to Upington in 4hr15min using 62 litres of fuel. It carried its two passengers and their luggage in comfort at 9500 feet altitude. The Automobile Association gives the road distance between these two cities as 1314km. By car the journey would likely take in excess of 13hrs.
The actual aircraft that undertook the flight is shown in the attached was designed and built in the Eastern Cape.

Tuesday, May 3, 2011

Hydro energy harvester Mk 2

Riaan Opperman is researching zero head hydro devices for his Masters project. His aim is to come up with a viable energy harvester using river flow alone. This energy can obviously be used for a variety of purposes, however pumping water is the most obvious! Many zero head hydro devices have been experimented with in the past ranging from underwater propellers to oscillating aerofoils etc etc however the one that looked particularly practical and promising was the helical pipe pump due mainly to its lack of wearng parts, ability to survive floating debris and its sheer simplicity. We had to build one!!
Pics show some of the assembly and initial trials. So far performance looks promising with approximately 450 litres per hour pumped to 10m head from a river flow of about 0.75m/s. More precise measurements to follow as well as performance tweaking...