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  Reply # 2032308 8-Jun-2018 18:46
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tripper1000:

 

kryptonjohn: That said, if they ever shut down Tiwai Point smelter, this could be a good use for the Manapouri hydro power, given it is in the "wrong" part of the country.

 

Global warming and CO2 is a global problem. Shutting down Tiwai Pt and re-appropriating Manapouri is a foolish environmental move. It will solve zero on a global scale because the Aluminum it fails to make will instead be made in a coal powered smelter in China/Australia/USA/Russia.

 

The world is always going to need aluminum, and it takes a lot of electricity to make aluminum. If NZ wants to be a responsible global citizen that contributes to reducing CO2 in a meaning full way, while growing our economy, we need to be building 10 more Manapouri's, building new Aluminum Smelters and putting the dirty coal powered smelters out of business.

 

The problem at the moment is we don't have the gumption of our parents/grandparents who built all the hydro dams. Even though hydro is the goose that lays golden eggs, and right when the fate of the world depends on it we can't seem to pull finger and build some more.

 

 

Exactly. Its true that greenies dont want that, pity as you alluded to in the previous post, a hydro installation isnt taking over the world. Its vastly altering a very small plot. The result is reducing effect on other plots. I posted a link on the EV thread that solar PV is choking AUS electricity grid. 

 

Ill grab it now

 

https://www.stuff.co.nz/business/world/104522072/surge-in-solar-power-is-flooding-australias-national-grid

 

If we can work toward this...




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  Reply # 2032336 8-Jun-2018 20:21
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tripper1000:

 

frednz:

 

But EV manufacturers are now rapidly moving towards producing EVs with higher capacity batteries (e.g. 64 kWh Hyundai Kona due here soon). And the higher the capacity of lithium batteries, the greater the amount of electricity that is needed to charge them up. And at the moment, NZ has not withdrawn the use of coal for the generation of electricity, so if the demand on the electricity network becomes too great, then coal is used, which sort of defeats one of the main purposes of an electric car, which is to reduce harmful emissions.

 

The assumption in this statement aren't quite correct and based on long debunked theories the the media likes to repeat:

 

1) Coal is used in NZ to meet peak demand which is mostly 9am till noon weekdays (unless we have a dry year and the lakes are low). Most people are at work at those times, NOT charging their cars because 80% of people charge their BEV's at home. As a side and adding to the point, most EV users with the choice are on a night and day plan, meaning power in the small hours of the morning (off peak) is cheaper. So the vast majority of EV's are charged when the coal stations are not running, meaning operating EV propulsion systems in NZ produces zero CO2.

 

 

Sure, at the moment, the use of coal for electricity generation may not have a lot to do with EV battery recharging. But, what I had in mind when I said "if the demand on the electricity network becomes too great" was, what is going to happen when EV numbers grow substantially in the future? Will NZ be able to withdraw the use of coal for the generation of electricity if EV numbers grow as predicted?

 

The topic of how the grid might be able to handle a large increase in the number of EVs is discussed in this article:

 

http://www.infometrics.co.nz/big-ev-fleet-can-new-zealands-grid-handle/

 

Extract from above:

 

With a fleet of four million cars, vans, utes, small trucks, and large trucks, charging all these vehicles could take up almost the entire currently installed generation capacity we have for electricity. 

 

So, it's not just a case of thinking about the number of EVs we have now, but what's going to happen when a large number of EVs are on our roads!

 

 

 

 




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  Reply # 2032346 8-Jun-2018 20:43
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tripper1000:

 

frednz:

 

With the synthetic fuel that can be manufactured from CO2 pulled out of the atmosphere, it can be blended or used on its own as gasoline, diesel, or jet fuel. The main problem is that, when it’s burned, it emits the same amount of CO2 that went into making it, so although it’s effectively carbon neutral, it's still emitting CO2 into the atmosphere.

 

 

This is not the main problem - the problem is not as simple as CO2 being emitted into the atmosphere. The problem is the origin of the carbon. Ancient carbon being extracted and turned into CO2 is adding to the total CO2. If I take carbon out of the atmosphere and soon after put it back in, I have not added to nor subtracted from the carbon in the atmosphere - I am therefore carbon neutral and not contributing toward the problem.

 

 

But is "ancient carbon" being extracted by the Canadian company "Carbon Engineering"?

 

I agree that if carbon is taken out of the atmosphere and is soon after put back in by burning the "carbon neutral" liquid fuel, this hasn't added to the amount of carbon in the atmosphere. But, wouldn't it be a whole lot better if companies that can extract large amounts of carbon from the atmosphere didn't "soon after put it back in"?

 

Shouldn't the overall aim be to somehow reduce the overall amount of carbon in the atmosphere, not just maintain the amount that is already there?

 

 

 

 

 

 


gzt

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  Reply # 2032376 8-Jun-2018 22:18
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It would stop more being added and that would be an achievement.

then depends how many tons sitting in tankers, gas stations and petrol tanks waiting to be used. At maximum replacement the tech would 'sequester' that much.

Overall sounds a bit silly. Maybe the base tech will have a practical use somehow somewhere for meaningful reduction. There is some potential. Bill Gates is an investor.



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  Reply # 2032435 9-Jun-2018 09:42
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frednz:

 

tripper1000:

 

frednz:

 

With the synthetic fuel that can be manufactured from CO2 pulled out of the atmosphere, it can be blended or used on its own as gasoline, diesel, or jet fuel. The main problem is that, when it’s burned, it emits the same amount of CO2 that went into making it, so although it’s effectively carbon neutral, it's still emitting CO2 into the atmosphere.

 

 

This is not the main problem - the problem is not as simple as CO2 being emitted into the atmosphere. The problem is the origin of the carbon. Ancient carbon being extracted and turned into CO2 is adding to the total CO2. If I take carbon out of the atmosphere and soon after put it back in, I have not added to nor subtracted from the carbon in the atmosphere - I am therefore carbon neutral and not contributing toward the problem.

 

 

But is "ancient carbon" being extracted by the Canadian company "Carbon Engineering"?

 

I agree that if carbon is taken out of the atmosphere and is soon after put back in by burning the "carbon neutral" liquid fuel, this hasn't added to the amount of carbon in the atmosphere. But, wouldn't it be a whole lot better if companies that can extract large amounts of carbon from the atmosphere didn't "soon after put it back in"?

 

Shouldn't the overall aim be to somehow reduce the overall amount of carbon in the atmosphere, not just maintain the amount that is already there?

 

 

The concept of not releasing "captured carbon" back into the atmosphere by burning "carbon neutral" synthetic fuels is discussed in this article:

 

https://www.technologyreview.com/s/611369/maybe-we-can-afford-to-suck-cosub2sub-out-of-the-sky-after-all/

 

"But those carbon-neutral fuels won’t directly help to reduce carbon in the atmosphere (unless they’re used in systems that capture carbon as well). To make real gains in removing greenhouse gases, the world may eventually need to permanently store massive amounts of captured carbon dioxide, rather than releasing it again when synthetic fuels burn. Doing that on a large scale would almost surely require significant cost reductions, a high price on carbon, or other public policy support."

 

So the focus needs to be on how to permanently store huge amounts of captured carbon dioxide from the atmosphere if we are going to make real advances in combatting global warming.


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  Reply # 2032722 9-Jun-2018 20:16
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frednz:

 

tripper1000:

 

While it is cool and interesting that they can pull CO2 out of the atmosphere, when all said and done this is just a convoluted, expensive and inefficient way to store electrical energy.

 

Even if the fuel creation process was 100% efficient, which it can't be, the engines in the vehicles that are burning the fuel are only 20% to 30% efficient so at minimum 70% of your electrical energy is being wasted.

 

It is the same reason that Hydrogen Cells aren't really making the impact that Lithium batteries cars are - it takes loads of electricity to make hydrogen and batteries are simply a far more efficient system for storing electrical energy.

 

 

 

 

But EV manufacturers are now rapidly moving towards producing EVs with higher capacity batteries (e.g. 64 kWh Hyundai Kona due here soon). And the higher the capacity of lithium batteries, the greater the amount of electricity that is needed to charge them up. And at the moment, NZ has not withdrawn the use of coal for the generation of electricity, so if the demand on the electricity network becomes too great, then coal is used, which sort of defeats one of the main purposes of an electric car, which is to reduce harmful emissions.

 

With the synthetic fuel that can be manufactured from CO2 pulled out of the atmosphere, it can be blended or used on its own as gasoline, diesel, or jet fuel. The main problem is that, when it’s burned, it emits the same amount of CO2 that went into making it, so although it’s effectively carbon neutral, it's still emitting CO2 into the atmosphere.

 

 

 

 

Yes agree tripper the idea is flawed just like the hydrogen fuel cell tech.I walked down a busy road yesterday and after about 10 minutes the stench of the fossil fuels being burned was quiet disturbing.I can imagine how I would feel if I was pushing a pram with a baby that I would want to get a child the hell out of there.Frednz, about not enough hydro to support charging is not correct in my opinion.Solar panels will help solve  that issue and wind and solar as well as tidal power will also if needed.The ney sayers said this would happen in Britain and it has not been an issue.


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  Reply # 2032821 10-Jun-2018 09:13
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Solar is not going to provide large scale electricity generation in NZ. Simply because peak demand is early mornings, and winter evenings. So solar doesn't reduce the amount of generation capacity that you need to build.

And apart from a few days in summer where there is significant air conditioning load. Solar output profile is the opposite of the load profile. For example the weather right now is cloudy. Since it is also winter, I need to have my heater running. Any solar panels right now would only be producing around 10% of their rated output. If the weather was instead sunny, I wouldn't need to have the heater running, as the sun would warm up my house.

Also you need to provide renewable generation that is also cheap. Hydro can do that, solar can't. As expensive electricity simply means that lots of people use fossil fuels for heating instead of electricity. And also consider the power used for things like bitcoin mining, web hosting, or anything else that is done by computers. Data centers get built in countries with cheap electricity, which is often fossil fuel generated.

NZ could easily have both really cheap electricity, and have it almost completely renewable generated. But we will have to accept that it will mean more hydro and wind generation.

Have a look at the 3 gorges dam project in China. 1 hydro power station that has more generation capacity than the combined output of every nuclear power station in the USA.

And back in NZ, I have heard claims that NZ will run out of natural gas in 7 to 10 years, due to the silly oil drilling ban. We need to start constructing large scale hydro and geothermal right now. Yet I'm not aware of any announcements of new renewable generation, that will be constructed. Instead we will either have to build more coal fired generation to replace the gas fired generation. Or we will just have rolling blackouts whenever there is a dry year. Meaning that rich people will just buy diesel generators and poor people will freeze.





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  Reply # 2032969 10-Jun-2018 12:04
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I think statements like this are way too pessimistic. They try to make extrapolations based on current technology. But if there is one thing we ought to have learned from history, it is that technology doesn't stand still.

 

I am not an engineer and the Internet is full of fantastical nonsense, so I won't try to include any references. Those who are interested can find plenty with simple Google searches. I do know that different materials, even sand and ice, are being researched as heat storage media. I also know that Stirling engines have been developed that operate on very low temperature differentials. I strongly believe in the principle that solutions can be found to any technological problem. The limitations of solar are not insurmountable. Photoelectric is only part of the answer. Solar heat generation and storage, coupled with efficient temperature differential engines, can be another part. Things we haven't even heard of yet will be another. This is a transitional period.





I reject your reality and substitute my own. - Adam Savage
 


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  Reply # 2032970 10-Jun-2018 12:05
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Aredwood: Solar is not going to provide large scale electricity generation in NZ. Simply because peak demand is early mornings, and winter evenings. So solar doesn't reduce the amount of generation capacity that you need to build.

And apart from a few days in summer where there is significant air conditioning load. Solar output profile is the opposite of the load profile. For example the weather right now is cloudy. Since it is also winter, I need to have my heater running. Any solar panels right now would only be producing around 10% of their rated output. If the weather was instead sunny, I wouldn't need to have the heater running, as the sun would warm up my house.

Also you need to provide renewable generation that is also cheap. Hydro can do that, solar can't. As expensive electricity simply means that lots of people use fossil fuels for heating instead of electricity. And also consider the power used for things like bitcoin mining, web hosting, or anything else that is done by computers. Data centers get built in countries with cheap electricity, which is often fossil fuel generated.

NZ could easily have both really cheap electricity, and have it almost completely renewable generated. But we will have to accept that it will mean more hydro and wind generation.

Have a look at the 3 gorges dam project in China. 1 hydro power station that has more generation capacity than the combined output of every nuclear power station in the USA.

And back in NZ, I have heard claims that NZ will run out of natural gas in 7 to 10 years, due to the silly oil drilling ban. We need to start constructing large scale hydro and geothermal right now. Yet I'm not aware of any announcements of new renewable generation, that will be constructed. Instead we will either have to build more coal fired generation to replace the gas fired generation. Or we will just have rolling blackouts whenever there is a dry year. Meaning that rich people will just buy diesel generators and poor people will freeze.

 

Re  https://www.stuff.co.nz/business/world/104522072/surge-in-solar-power-is-flooding-australias-national-grid

 

Yes, we are no Australia, but this article seems to show that Residential solar can be large. Too large that they get too much. In NZ, a lot of residential solar can reduce hydro water use? In weekends, more are home, so more lake level savings? Yes, while thats replacing green energy with other green energy, if we can make some savings on lake levels, we should reduce power spikes. Plus, absorb growing EV. Plus for citizens, there is a $ saving, good for the economy. If we need more hydro installations in the future, maybe we can save building one of them. 


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  Reply # 2033014 10-Jun-2018 13:18
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For most people, grid Connect solar is a means of saving on lines fees, more than a saving on energy costs. Due to the silly system where lines fees are billed as a surcharge on the energy costs, instead of a separate fixed fee or capacity based fee.

If the low user regulations were repealed, Fixed lines fees could increase to around $4- $5 per day. And per unit costs could drop to less than 10c per unit. Total bill cost would still be similar for someone using around 8000 units per year. But solar users would complain about not saving as much. Although it would also allow Nett metered solar price plans to re appear.

NZ also doesn't have anywhere near enough hydro storage to properly use large scale solar. Storage is only in the region of a few weeks to a month of generation capacity. Meaning a big storm can easily fill the lakes. While a dry year can still cause a winter power shortage, even if the lakes were full in April.

We would need hydro storage equivalent to around 6 months of demand for large scale solar to be useful. We would probably need a lake of similar size to Lake Superior in the USA for that to happen.

And is solar still economic to install if grid power cost around 10c per unit? How about 5c per unit? And if you give subsidies to solar, is that actually the best way of reducing carbon emissions? Is such money better spent on say subsidies for buying EVs?

Either way, something needs to change. As high power prices are a subsidy for fossil fuels. As they are cheaper in comparison. And are also an unnecessary extra cost on EV charging.





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  Reply # 2033019 10-Jun-2018 13:31
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I'd love to see more big hydro projects - clean power with the by-product of fantastic recreational facilities for sailing, fishing etc.  But these days there always seems to be a unique breed of snail, or some other reason why they can't be built.


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  Reply # 2033048 10-Jun-2018 14:50
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Aredwood: F
NZ also doesn't have anywhere near enough hydro storage to properly use large scale solar. Storage is only in the region of a few weeks to a month of generation capacity. Meaning a big storm can easily fill the lakes. While a dry year can still cause a winter power shortage, even if the lakes were full in April.

We would need hydro storage equivalent to around 6 months of demand for large scale solar to be useful. We would probably need a lake of similar size to Lake Superior in the USA for that to happen.

And is solar still economic to install if grid power cost around 10c per unit? How about 5c per unit? And if you give subsidies to solar, is that actually the best way of reducing carbon emissions? Is such money better spent on say subsidies for buying EVs?

Either way, something needs to change. As high power prices are a subsidy for fossil fuels. As they are cheaper in comparison. And are also an unnecessary extra cost on EV charging.

 

Does that still apply if you have an alternative like wind generation? Wind increase during winter, when electricity demand increases.

 

I don't see EVs as an alternative to solar to reduce emissions. I see EVs and home solar and PowerWall as to symbiotic technologies which, for the energy consumer, multiply the cost savings available from each separate technology. Batteries allow time-shifting of consumption away from time of generation. So a home solar generation system charges batteries which can then be used for energy at peak load times. And, given sufficient solar generation, to also supply power to charge your car for use the next day.

 

 


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  Reply # 2033141 10-Jun-2018 16:44
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tripper1000:

 

1) Coal is used in NZ to meet peak demand which is mostly 9am till noon weekdays (unless we have a dry year and the lakes are low). Most people are at work at those times, NOT charging their cars because 80% of people charge their BEV's at home. As a side and adding to the point, most EV users with the choice are on a night and day plan, meaning power in the small hours of the morning (off peak) is cheaper. So the vast majority of EV's are charged when the coal stations are not running, meaning operating EV propulsion systems in NZ produces zero CO2.

 

 

Can you prove a source for this.  When  I was at tech, I was taught that thermal stations did not like the thermal shock of being turned on and off twice per day. It vastly reduced their life expectancy.  Instead, they were run at constant capacity, and hydro provide for peak power, as their turbines did not mind being varied through out the day.  


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  Reply # 2033168 10-Jun-2018 18:03
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Thanks, guys, for sharing your knowledge and obvious intelligence. Excuse the pun, bit it is illuminating.

 

 


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  Reply # 2033205 10-Jun-2018 18:36
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debo:

 

Can you prove a source for this.  When  I was at tech, I was taught that thermal stations did not like the thermal shock of being turned on and off twice per day. It vastly reduced their life expectancy.  Instead, they were run at constant capacity, and hydro provide for peak power, as their turbines did not mind being varied through out the day.  

 

 

I went to a presentation a few years ago about a new gas-powered turbine that was being installed at Huntly - that was going to be base load, ie on 24/7, presumably for the reason you mention.  Although gas turbines are usually better at stop/start than coal plants, which have steam as the driving force


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