Visit to Porterville: Friday 15th April 2016.

The original appointment was somewhere in March but that had to be canceled due to inclement weather. The event was to have consisted of a talk at the retirement home, Huis Nerina, in the afternoon followed by a stargazing event at the Golf Course in the evening. The bad weather would not have affected the talk at Huis Nerina but would certainly have prevented the stargazing. So the event was rescheduled for Friday the 15th, which unfortunately clashed with an appointment we had with the EcoRangers in the Helderberg Nature Reserve (click here to visit their webpage and find out more about this magnificent corner of South Africa) . Rather than cancel one of the events we decided to split up. Auke would do the presentation for the EcoRangers (click here to find out more about the EcoRangers) while Lynnette, Snorre and I would go to Porterville and do Huis Nerina and the Golf Course stargazing. Nathalie, from Porterville Tourism, (click here to visit their webpage) (you can also visit their FaceBook page by clicking here) contacted us shortly after these arrangements had been made and told us that the Porterville event would have to be shifted to Thursday the 14th because there was a dance on in the town and people wanted to attend that and our stargazing event. This actually suited us because we would not have to split up and could all three do both events. This was not to be because, a few days later, an embarrassed Nathalie contacted us and asked if we would please be prepared to switch back to Friday the 15th as some other administrative glitch had popped up! So, because we try and please most of the people most of the time, we switched back to splitting StarPeople up.

On Friday morning Lynnette, Snorre and I set off to Porterville where we arrived around 11:00 and reported to Nathalie at the Tourism Office.  From there we went to the Rendezvous B&B, Restaurant (visit a webpage with more information about this very friendly establishment) where we were welcomed by Riana van der Merwe and shown to our room. One of the staff, appropriately named Angel, quickly converted the two twin beds to a double bed. Shortly after 14:00 we headed for Huis Nerina and Old Age Home run by the ACVV, leaving Snorre in our room. The ACVV is the oldest welfare organization in South Africa, having been established in 1904 to render a comprehensive social welfare service to families in need (click here for more information on the ACVV) At Huis Nerina we discovered that there was no convenient white wall to project against, as we had been assured there would be. The staff quickly found a bed sheet and in no time it was fixed to a wall with sellotape and funny putty.

My talk was on astronomy in South Africa with some extra slides thrown in of pretty astronomical objects and a bit of Stellarium. I also asked the folks to encourage all grandchildren and great-grandchildren who had any interest in Science, Technology, Engineering, and Mathematics to stick with it and qualify themselves to participate in South Africa’s blooming astronomy endeavors. After fielding some questions we packed and said goodbye up after promising to come back with a telescope and do some real astronomy with them somewhere in the future.

A special note on the photographs in this post: Lynnette was the photographer but using my camera and somehow most of the photographs are just ever so slightly out of focus. Neither of us knows why because my photographs later on of the flowers are fine. Lynnette is not happy about the quality of her photographs but next time we will check the camera out first.

TOP LEFT: Entrance gate to Huis Nerina the retirement home in Porterville, run by the ACVV. TOP RIGHT: The assembled Golden Oldies. Please note the makeshift laptop and projector stand at centre right. BOTTOM LEFT: Different view with me in the picture. BOTTOM RIGHT: Almost the same as the top right one but from a slightly different angle and zoomed in a little bit.
TOP LEFT: Entrance gate to Huis Nerina the retirement home in Porterville, run by the ACVV. TOP RIGHT: The assembled Golden Oldies. Please note the makeshift laptop and projector stand at centre right. BOTTOM LEFT: Different view with me in the picture. BOTTOM RIGHT: Almost the same as the top right one but from a slightly different angle and zoomed in a little bit.

After a trip back to the Rendezvous for refreshments, we pitched at the golf course at around 18: to start setting up. Snorre was unfortunately confined to barracks because we were worried that some of the visitors might bring dogs, as they had on our previous visit. We were right because there was a particularly industrious Dachshund who felt duty bound to bark loudly at everything and everyone. Not Snorre’s cup of tea I am afraid.

TOP LEFT: The guest used chairs from the Golf Club and many brought blankets for their children. TOP RIGHT: The guests listening to me. The white objects most of them appear to be holding are the supper parcels Nathalie organized. CENTER: StarPeople’s banners displayed in the well-lit area in front of the door leading to the bar and the loo. BOTTOM LEFT: A different angle on the guests with me in the picture just to prove that I was there. BOTTOM RIGHT: Shot from behind you can see that it was pretty dark there despite several really irritating street lights.
TOP LEFT: The guest used chairs from the Golf Club and many brought blankets for their children. TOP RIGHT: The guests listening to me. The white objects most of them appear to be holding are the supper parcels Nathalie organized. CENTER: StarPeople’s banners displayed in the well-lit area in front of the door leading to the bar and the loo. BOTTOM LEFT: A different angle on the guests with me in the picture just to prove that I was there. BOTTOM RIGHT: Shot from behind you can see that it was pretty dark there despite several really irritating street lights.

By 19:15 the guests started trickling in and shortly after 19:30 I kicked off with a short talk before starting the telescope viewing. Orion was on its way down and already fairly low in the west so we started with M45, the Orion Nebula) and then worked our way eastward covering Jupiter and the Moon before switching to the Crux, the Diamond Cross and various objects of interest in the Milky Way itself.

TOP LEFT: Some guests did some naked eye stargazing while standing in line for a look through the telescopes. TOP RIGHT: We were very happy to see quite a few children among the guests. CENTER: Myself, Lorenzo and the ever-cheerful Nathalie Wagenstroom the Tourism Officer at Porterville Tourism. BOTTOM LEFT: I must say the guests were not only very interested but many of them were also quite clued up. BOTTOM RIGHT: There were one or two guests who appeared to be a little apprehensive about looking through the telescope.
TOP LEFT: Some guests did some naked eye stargazing while standing in line for a look through the telescopes. TOP RIGHT: We were very happy to see quite a few children among the guests. CENTER: Myself, Lorenzo and the ever-cheerful Nathalie Wagenstroom the Tourism Officer at Porterville Tourism. BOTTOM LEFT: I must say the guests were not only very interested but many of them were also quite clued up. BOTTOM RIGHT: There were one or two guests who appeared to be a little apprehensive about looking through the telescope.

Some sharp-eyed star gazers spotted Arcturus rising and mistook that for Mars which kindly put in an appearance a little while later, followed even later by Saturn. Once again one had proof positive that trying to view objects that had just risen above the horizon might have artistic merit but was an astronomical waste of time. By 22:30 we had packed up and not too long after 23:00 we could shower and hit the bed with a vengeance. Snorre was glad to see us but clearly perplexed at not being able to accompany us.

TOP LEFT: Some guests did some naked eye stargazing while standing in line for a look through the telescopes. TOP RIGHT: We were very happy to see quite a few children among the guests. CENTER: Myself, Lorenzo and the ever-cheerful Nathalie Wagenstroom the Tourism Officer at Porterville Tourism. BOTTOM LEFT: I must say the guests were not only very interested but many of them were also quite clued up. BOTTOM RIGHT: There were one or two guests who appeared to be a little apprehensive about looking through the telescope.
TOP LEFT: Some guests did some naked eye stargazing while standing in line for a look through the telescopes. TOP RIGHT: We were very happy to see quite a few children among the guests. CENTER: Myself, Lorenzo and the ever-cheerful Nathalie Wagenstroom the Tourism Officer at Porterville Tourism. BOTTOM LEFT: I must say the guests were not only very interested but many of them were also quite clued up. BOTTOM RIGHT: There were one or two guests who appeared to be a little apprehensive about looking through the telescope.

After a leisurely breakfast the next morning we packed up and headed home. We only stopped to photograph some Brunsvigia Orientalis (Afrikaans: Koningskandelaar) and Crassyn guttata (Afrikaans: Sambreelblom) in a field adjacent to the road near Halmanshof. Once home it was the usual schlep of unloading and packing everything away before being able to relax.

TOP LEFT: Crassyn guttata (Afrikaans: Sambreelblom). TOP RIGHT: The inflorescence of Brunsvigia orientalis (Koningskandelaar) shortly after pushing its way into the open. CENTER: A whole field of these flowers and you can sort through to identify them. BOTTOM LEFT: Brunsvigia orientalis on the left and Crassyn guttata on the right. BOTTOM RIGHT: A cluster of Crassyn guttata.
TOP LEFT: Crassyn guttata (Afrikaans: Sambreelblom). TOP RIGHT: The inflorescence of Brunsvigia orientalis (Koningskandelaar) shortly after pushing its way into the open. CENTER: A whole field of these flowers and you can sort through to identify them. BOTTOM LEFT: Brunsvigia orientalis on the left and Crassyn guttata on the right. BOTTOM RIGHT: A cluster of Crassyn guttata.

We will try and organize a special trip for the residents of Huis Nerina around the First Quarter Moon to give them the opportunity of looking through a telescope. Maybe Nathalie can pull a few strings for us.

 

The Gouda Wind Farm: April 2015

A new wind farm has been taking shape at Gouda in the Drakenstein Municipality of the Western Cape.

When Lynnette and I recently went to Porterville for the stargazing event at the Porterville Golfclub, organized by Nathalie Wagenstroom from the Porterville Tourism Office, I hadn’t been out that way for quite some time. I was therefore surprised to find that a new wind farm had sprouted up to the right of the R44 just past where it crosses the railway line.

This wind farm will consist of forty-six 100 m towers each carrying a 3 MW Acciona wind-power turbine so that the site can produce 138 MW at full capacity. The construction started in 2013 and was scheduled for completion in 2014 with the power being delivered to a 132 kV distribution network at the Windmeul substation near Wellington. Go here to read more about the project in the August edition of Engineering News. You will find a comprehensive overview of the project as summarized in the August 2013 NERSA public hearings. There is more information here on the webpage of Energy4Africa. Driving past there it was clear that they are way behind schedule.

Top left: View of the wind-farm from the R44 before reaching the turnoff to Gouda and Porterville. Top right: View of the wind-farm from the R44 just after turning off to Gouda and Porterville. Bottom left: The R44 passes right next to these enormous. structures. Bottom right: The wind-farm from the top of the bridge that takes the R44 over the railway line.
Top left: View of the wind-farm from the R44 before reaching the turnoff to Gouda and Porterville.
Top right: View of the wind-farm from the R44 just after turning off to Gouda and Porterville.
Bottom left: The R44 passes right next to these enormous. structures.
Bottom right: The wind-farm from the top of the bridge that takes the R44 over the railway line.

The Gouda Wind Facility is the first wind farm in South Africa to use concrete towers. Steel towers are imported while concrete towers can be manufactured locally. Another advantage is that one can build taller towers, up to 120 m, at a reduced energy cost. The wind farm at Hopefield consists of thirty-seven, 95 m steel towers each carrying a 1.78 MW turbine from the Danish firm Vestas. The installation will produce 66 MW at full capacity. Go here to read about the installation in the May 2014 edition of Engineering News.

Hopefield wind powered generators on our way home
Hopefield wind powered generators.

The Gouda installation was erected by Acciona Energy and Aveng while Sarens supplied the equipment to transport and lift the various sections of the towers as well as the turbine blades and the turbines. At full capacity Gouda will supply enough power for 146 000 low income homes or 60 000 medium income homes.

Top left: Acciona's 3 MW turbines are as large as a medium sized caravan and perch on top of a 100 m concrete column. Top right: The parked vehicles give one an idea of the size of these structures. Bottom left: Another attempt at giving you an idea of the size of those columns. Bottom right: The previous photo enlarged and, in case you missed him there is a person wearing a yellow construction vest in the structure next to the tower.
Top left: Acciona’s 3 MW turbines are as large as a medium sized caravan and perch on top of a 100 m concrete column.
Top right: The parked vehicles give one an idea of the size of these structures.
Bottom left: Another attempt at giving you an idea of the size of those columns.
Bottom right: The previous photo enlarged and, in case you missed him there is a person wearing a yellow construction vest in the structure next to the tower.

Each blade of the three-blade turbine is 50 m long and the pitch of the blades is increased as wind speed drops to increase the torque and maintain the rotation speed. If the wind speed increases the pitch will be decreased to reduce the torque. At wind speeds of around 20 m/s at the hub height (that is around 70 km/h) the turbines are shut down. In rural areas the turbine blades are required to generate no more than 35 decibels of sound which is classified as less noise than a normal conversation.

When one sees these turbine blades rotating they always look as if they are in slow motion. A bit of mathematics reveals that if the rotor is turning at 10 revolutions per minute the tips of those 50 m long blades are travelling at over 180 km/h. Low flying birds cannot judge the speed of those rotor tips correctly and, because the rotors taper, the tips are far less visible than the sections closer to the hub, so they fly into them, with fatal results. This is especially the case for large, slow birds like geese, pelicans, cranes and storks. Raptors tend to be watching for prey on the ground so they also often fall foul of the blades. From an environmental perspective, it is important that wind farms should not be built on the migration routes of these birds, or in areas where they congregate to feed or breed.