Jasper solar project in SA versus Medupi

boerseun said:
Germany learnt their lesson when it comes to renewable energy. Don't put that **** on your grid! Their grid s teetering on the verge of collapse and to make up for the shortfall when the sun goes bye bye, last year the amount of brown coal they burnt was the highest in 20 years. I hope the greens take note of that.
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I dont agree with you. Germany is in fact setting a brilliant example of how it should be done. They are getting rid of their nuclear plants and are increasing their dependence on renewable energy sources. Although Germany's average reliance on renewable energy is at about 30%, this past summer they produced 50% of the countries energy demand with solar power for the first time (22GW, or as much as 20 nuclear stations!). Yes, this was only for a day, during the summer when the days are long and electricity usage is lower, but still for one of the worlds most power hungry countries to be able to run 50% of the country on solar is quite something, and it shows the direction they are going. Also keep in mind this is not a very sunny place, not at all like the abundance of sun we have in the Karoo, so if it can be done here in Europe then I don't see why not in Sunny SA and the Windy Cape.

I live in Germany and it is really interesting to see how every second farm, farm house, outbuilding, everything has their own solar farms that sell solar energy back into the grid. What they did really well is incentivize the ordinary Joe Schmoe to set up their own private solar farms that sell electricity back into the grid, so they do not need these massive big projects with big failure risk to invest in solar.

I have always been skeptical about greens and their renewable energy sources, but I must admit the Germans have proven without a doubt that it is the way of the future, that it is doable and sustainable. Yes, it will probably never be the *only * energy source anytime during our life time, but the more we can get out of "free" energy the better for everyone.
 
SoftDux-Rudi said:
Just goes to show, coal is still the cheapest form of generating electricity. Solar will probably take another millennium to be cheaper than traditional ways of generating electricity.
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Actually, the end-price makes nuclear the cheapest form of power generation. Coal plants are relatively cheap to build, but expensive to run. Solar is expensive to build, but cheap to run. The solar plant will quickly pay for itself.

SoftDux-Rudi said:
And, at what cost is it a "greener" solution? How much electricity / carbon is wasted in the manufacturing and implementation process of this solar plant alone?
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http://www.popsci.com/science/article/2013-04/solar-panels-now-make-more-electricity-they-use
 
alexandergrahambell said:
I often wonder why the so-called "green" types never object to their beloved ecosystems being rendered effectively sterile by these thousands of solar panels. What happened to their "biodiversity" mantra? What about all the foliage that could still be absorbing CO2 that was eradicated to make space for all these panels? Did they perhaps burn it?! Then what about all the (coal-fired?) energy that goes into making these panels? How far were they transported using diesel-fuelled ships and trucks? Do the solar protagonists really take all these things into account when comparing high energy-density coal with their "eco-friendly" and "sustainable" energy dreams? Fusion energy has to come one day. In the meantime why not use what is readily available in the ground to fuel the economy that is needed to bring that day closer?
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Fusion is a minimum of fifty years away. The 'readily available' coal is reducing fast, and unpleasant to burn. As for all the 'energy that goes into making' and transporting these panels... do you think making a coal plant is free? What about all the fuel needed to transport the daily tons of coal it gobbles up?

Solar has its problems, but it's already massively cheaper and greener over the lifespan of a plant.
 
What about a hybrid coal-solar plant?

Coal at night or to cover shortfall of solar during daytime.

This way you will use less coal during daytime. At night the electricity usage will be low anyway.

It is only the pesky periods between sunrise and sunset when people make food, shower/bath, and is requesting more electricity from the grid...
 
Other than initial CAPEX and time to completion, what other benefits are there exactly for this particular Solar setup?
 
The problem with this article is that it stirs up debate of coal vs solar, so now people are posting anti-green vs pro-green type comments, while everyone is missing the real point.

1) We are getting more electricity on the Eskom grid which is extremely needed and therefor this is GOOD NEWS.

2) Secondly it is putting our "electricity eggs" in multiple baskets so to speak, so creating energy production variety which is exactly what we need more of.

3) Thirdly is that someone went out there and started to do Eskom's job for them by building new energy sources and getting it up and running quickly, while Eskom was too busy paying out bonuses to executives and picking their noses.

So as far as I can see, it is only good news all the way.
 
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The_Librarian said:
What about a hybrid coal-solar plant?

Coal at night or to cover shortfall of solar during daytime.

This way you will use less coal during daytime. At night the electricity usage will be low anyway.

It is only the pesky periods between sunrise and sunset when people make food, shower/bath, and is requesting more electricity from the grid...
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I once chatted to a engineer who'd worked on the Pebble Bed Reactor program. He had a much more intriguing and environmentally friendly concept. A Solar thermal plant that uses a pebble bed reactor as heat source for the turbines at night or during peak demand.

The ideal would be more efficient energy storage and transmission. Large scale photovoltaics to generate the power, but then storage of excess capacity using technology like Vanadium Flow Batteries, or selling it to countries in that are in night time.
 
lcbxx said:
Other than initial CAPEX and time to completion, what other benefits are there exactly for this particular Solar setup?
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Well, seeing as Medupi is supposed to burn 14.6 MT of coal a year, and this plant produces about a fiftieth of the power, I guess a benefit would be somewhat over 250000 tons of coal that doesn't need to be burned... a year.

Seems like a pretty good benefit to me.
 
The_Librarian said:
What about a hybrid coal-solar plant?

Coal at night or to cover shortfall of solar during daytime.

This way you will use less coal during daytime. At night the electricity usage will be low anyway.

It is only the pesky periods between sunrise and sunset when people make food, shower/bath, and is requesting more electricity from the grid...
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I could be very wrong here, but my understanding is that powering down and powering up a coal or nuclear plant is not as simple as throwing a switch. It takes a time to bring the boilers for coal up to power and then it needs to be synced to the grid and blah blah blah. Same with Koeberg. IIRC it normally takes a long time to bring it back online to full power after a refueling or maintenance?
 
My takeaway from this article is that the private sector can get serious **** done in a year.

That makes me more angry about our parastatals than I usually am.
 
Compton_effect said:
I once chatted to a engineer who'd worked on the Pebble Bed Reactor program. He had a much more intriguing and environmentally friendly concept. A Solar thermal plant that uses a pebble bed reactor as heat source for the turbines at night or during peak demand.
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Something like that - use the sun during the day, and switch over to alternative(s) should there not be enough incoming energy from the sun.

I see nothing wrong with this, you still use the Sun's energy when it's being supplied, and have a fallback should the Sun decide to play hide and seek.
 
Ockie said:
I could be very wrong here, but my understanding is that powering down and powering up a coal or nuclear plant is not as simple as throwing a switch. It takes a time to bring the boilers for coal up to power and then it needs to be synced to the grid and blah blah blah. Same with Koeberg. IIRC it normally takes a long time to bring it back online to full power after a refueling or maintenance?
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Correct.
 
Wraitholme said:
The solar plant is massively cheaper (and simpler, and safer) to run. Taking into account the Medupi cost overrun, the solar plant will already be cheaper in the first few years of its operational time.
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Not quite...

This solar plant produces 96MW power, 50 times less than Medupi. It cost 36 times less to build though.
To produce 4800MW solar power would cost R145 Billion! Then you have the issue of replacing batteries every 5 to 10 years. Were the batteries calculated into the R2.9 billion?
The article doesn't mention anything about batteries, or standby time, so let's assume the 96MW gets produced ONLY during daylight hours - which is about 5-6 hours in South Africa. On a good sunny day. The Western Cape can have cloudy days for a few days at a time, throughout the year. So let's add a 20% - 30% loss due to bad weather.

On my small experiment solar "plant", I have about 23% loss during the year due to bad weather. And I can only use about 50% of the battery current, i.e. on a 105ah battery I can use about 53ah current. And I need to replace that within 5 hours, which means I need 11Ah solar power. A 300W solar panel give 8-8.5A (more like 8.2) and they cost between R3000 and R5000, depending on what and where you buy them. Certain brands actually offer more current throughout the day than others, and even give some "juice" when it's cloudy or the sun is settings and not shining directly on the panel.
 
Very cool. Really drives home how Solar is not a replacement for Coal or Nuclear though
 
Compton_effect said:
I once chatted to a engineer who'd worked on the Pebble Bed Reactor program. He had a much more intriguing and environmentally friendly concept. A Solar thermal plant that uses a pebble bed reactor as heat source for the turbines at night or during peak demand.
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That would be a great solution
 
Of the people I know in the energy game, most seem to like the idea of pumped-storage hydroelectricity. It's efficient and works very well with renewables - any excess power (remember that if you don't use all the power for a renewable source, it's wasted) from solar/wind can be used to pump to storage, and hydroelectricity is brilliant to fill in the gaps, as you can spin up a multi-GW plant from idle to full in a few minutes.

http://en.wikipedia.org/wiki/Pumped-storage_hydroelectricity
 
elvis_presley said:
Of the people I know in the energy game, most seem to like the idea of pumped-storage hydroelectricity. It's efficient and works very well with renewables - any excess power (remember that if you don't use all the power for a renewable source, it's wasted) from solar/wind can be used to pump to storage, and hydroelectricity is brilliant to fill in the gaps, as you can spin up a multi-GW plant from idle to full in a few minutes.

http://en.wikipedia.org/wiki/Pumped-storage_hydroelectricity
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Yeah, it is a great approach. But South Africa's climate is not conducive to building (hydroelectric) dams
 
JStrike said:
Yeah, it is a great approach. But South Africa's climate is not conducive to building (hydroelectric) dams
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Our climate would take down the efficiency a few %, but it's still a viable option. But if the government can't even get a power station built, and dams are far more effort, so that scuppers that idea under the ANC :(
 
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