Flywheel instead of battery storage?

[J.P.M.]

I first visited Los Angeles around 1975. Since then it has been cleaned up immensely, first via CARB and then the EPA. And during that process most US car manufacturers claimed they would be driven into bankruptcy, would only be able to sell deathtrap subcompacts etc etc. But clean air was important to us and we did it - and it worked. And today cars are safer, more powerful and more efficient than ever.

I have a feeling history will repeat. As with any change there will be winners and losers.

Believe it or not, I think I'm on your side, and I try to walk the walk, but from where I sit, I'm not real hopeful for the angels of our better nature to hold sway against the great dumbing I see all around.

One thing on autos: If the Japanese hadn't eaten the Big Three's lunch with a better product, we'd still be driving around in crap similar to what they once produced. Foreign competition built a better mousetrap. The rest is history.

[billvon]

One thing on autos: If the Japanese hadn't eaten the Big Three's lunch with a better product, we'd still be driving around in crap similar to what they once produced. Foreign competition built a better mousetrap. The rest is history.

Agreed. One of the big arguments against the earliest CARB pollution restrictions is that you could not meet them without a catalytic converter - and those things had PLATINUM in them! Were those greenies completely insane?

Then Honda built the CVCC engine which met the requirements without a catalytic converter.

[J.P.M.]

Agreed. One of the big arguments against the earliest CARB pollution restrictions is that you could not meet them without a catalytic converter - and those things had PLATINUM in them! Were those greenies completely insane?

Then Honda built the CVCC engine which met the requirements without a catalytic converter.

And before the Honda engine, maybe some folks with some sway in the matter went out and bought Platinum futures before they threw their weight around the corridors of policy making.

[Dave3011]

Dave what you fail to understand for every watt hour of RE energy you must have a conventional source to replace it in a heart beat. That only doubles the cost and twice the complication. Other than hydro and some wind, RE will never come close to replacing conventional power generation. In the usa hydro is already maxed out and built. Wind is too unreliable costly, and too high high of maintenance cost.

Nuclear energy is the only answer, clean, passively safe, with a few million years of cheap fuel underneath your feet.

Yes I actually do understand the dilemma, just maybe less pessimistic as I'm beginning to see the benefits of having my own solar panels on my roof. Yes I still rely on utility power for 80% of my electricity needs for 1 month either side of the winter solstice. I've yet to see what impact the coming lengthening of days and intensifying sunlight will have, but am hoping to soon be relying on utility power for less than 65% of my needs.

Nuclear maybe one of our best shots at mitigating the inevitable end of fossilized sunshine, but many feel its just to dangerous. Nuclear reactors don't go bang every day or even every decade proponents will say - maybe twice a century or so. Not a bad track record for sure! We have a 2000MW nuclear reactor just north of Cape Town and its been safe for 4 decades. Still can't imagine the panic or devastation it would cause to Cape Town's 4.5 million inhabitants if something ever happened...

RE seems like a pathetic little drop in the ocean, but the reality is humanity won't have a choice in the long run, or maybe we will. The alternative to RE is for our numbers and energy consumption to decrease in line with the rate at which we can squeeze oil, coal and gas from the bowels of the earth. I'm not a tree hugger don't get me wrong - I'm just one of those people that want's the lights to stay on. After all energy is the oxygen our human civilization depends on....

[Dave3011]

Wow - SA sun is super sun? For Phoenix, Arizona a 1 kW DC system will give you about 1700 kWh per year. Your sun and insolation are not that much different. I have looked at the SA insolation numbers before and they are good but 7 max as I remember

Well yes we get our light from the same star. Southern hemisphere receives a little more annual insolation than northern due the perihelion taking place on 3rd January. Atmosphere is also clearer due to lower population levels and lack of mixing across the equator. Lower temperatures in the southern hemisphere also mean less haze. Most of our land is also at significant altitude. The insolation maps I've seen give the desert areas in the Northern Cape an average annual ground level irradiance of >2300Kw/h per m2.
I know all of this doesn't make it a "super sun" but it does win the dick size contest

[russ]

The insolation maps I've seen give the desert areas in the Northern Cape an average annual ground level irradiance of >2300Kw/h per m2.
I know all of this doesn't make it a "super sun" but it does win the dick size contest

Better look again - no place on earth gets that kind of insolation - that is even more than 50% higher than the top of the earth's atmosphere.

I have flown over SA a few times - forget the clean atmosphere line - Africa is a mess from north to south.

[russ]

Nuclear maybe one of our best shots at mitigating the inevitable end of fossilized sunshine, but many feel its just to dangerous. Nuclear reactors don't go bang every day or even every decade proponents will say - maybe twice a century or so. Not a bad track record for sure! We have a 2000MW nuclear reactor just north of Cape Town and its been safe for 4 decades. Still can't imagine the panic or devastation it would cause to Cape Town's 4.5 million inhabitants if something ever happened...

Quit reading the green baloney - I wasn't aware that " many feel its just to dangerous" is an engineering term. To me it is a meaningless statement.

[Dave3011]

Better look again - no place on earth gets that kind of insolation - that is even more than 50% higher than the top of the earth's atmosphere.

I have flown over SA a few times - forget the clean atmosphere line - Africa is a mess from north to south.

I'm very interested to know where you get your figures from?

The solar constant at Earth's orbit in space varies between 1.412 kW/m² in early January to 1.321 kW/m² in early July. The top of the atmosphere averages 400w/m² between the tropics. At 28 degrees south latitude (Northern Cape) it is 380w/m² at the top of the atmosphere. 380*24*365 = 3328.8kwh/m². Add in an atmosphere and some very occasional cloud cover and 2300 is not a big ask.

Oh yes it is very very clear in the Northern Cape. Think you may have flown over Joburg which of course is a big dirty city. Not so when you get a few hundred miles away in the NC which is upwind in prevailing conditions...

[J.P.M.]

Well yes we get our light from the same star. Southern hemisphere receives a little more annual insolation than northern due the perihelion taking place on 3rd January. Atmosphere is also clearer due to lower population levels and lack of mixing across the equator. Lower temperatures in the southern hemisphere also mean less haze. Most of our land is also at significant altitude. The insolation maps I've seen give the desert areas in the Northern Cape an average annual ground level irradiance of >2300Kw/h per m2.
I know all of this doesn't make it a "super sun" but it does win the dick size contest

Looks and sounds like we're back on this units thing again. Something is still amiss here. That irradiance level you claim is about 3+ orders of magnitude more than I learned it to be. Maybe I'm wrong. If so, could you check your units and dimensions, and I'll check my unit and we'll have another contest ?

[J.P.M.]

I'm very interested to know where you get your figures from?

The solar constant at Earth's orbit in space varies between 1.412 kW/m² in early January to 1.321 kW/m² in early July. The top of the atmosphere averages 400w/m² between the tropics. At 28 degrees south latitude (Northern Cape) it is 380w/m² at the top of the atmosphere. 380*24*365 = 3328.8kwh/m². Add in an atmosphere and some very occasional cloud cover and 2300 is not a big ask.

Oh yes it is very very clear in the Northern Cape. Think you may have flown over Joburg which of course is a big dirty city. Not so when you get a few hundred miles away in the NC which is upwind in prevailing conditions...

Dave: Seriously, I mean no disrespect by this but you're embarrassing yourself. Check a solar textbook.

[Dave3011]

Dave: Seriously, I mean no disrespect by this but you're embarrassing yourself. Check a solar textbook.

http://www.greenrhinoenergy.com/solar/radiation/images/World%20Insolation%20Direct.jpg

Just a random google yielded this map. Never seen this particular map before but it proves my point. Not embarrassed just yet. I know how to add, subtract, multiply and divide just fine.

No disrespect to anyone on here - I reakon perhaps we are just not comparing apples with apples. Innocent misunderstanding maybe.

All the best,
D

[J.P.M.]

http://www.greenrhinoenergy.com/sola...n%20Direct.jpg

Just a random google yielded this map. Never seen this particular map before but it proves my point. Not embarrassed just yet. I know how to add, subtract, multiply and divide just fine.

No disrespect to anyone on here - I reakon perhaps we are just not comparing apples with apples. Innocent misunderstanding maybe.

All the best,
D

Have it your way.

[russ]

http://www.greenrhinoenergy.com/sola...n%20Direct.jpg

Just a random google yielded this map. Never seen this particular map before but it proves my point. Not embarrassed just yet. I know how to add, subtract, multiply and divide just fine.

No disrespect to anyone on here - I reakon perhaps we are just not comparing apples with apples. Innocent misunderstanding maybe.

All the best,
D

Best to stay away from sites that give information like that - you say you are an engineer - you well know what you end up with when you start with bad data. They are providing an annual total kW/m2 which no one uses.

Your point is wrong! Look at http://www.gaisma.com/en/

[inetdog]

It is indeed a matter of units.
The OP's original units of kW/h/m² are nonsensical and meaningless.
A reasonable set of units would be kWh/year/m², and it appears that is what he is trying to quote.
His supplemental number assumes a position in space in Earth's orbit which is facing the sun 24 hours per day. When you correct for the insolation at the surface, and the decreased time factor the numbers on the map are plausible.
Just do not confuse the "well known" figure of 1000w/m² with the xxxx kWh/m²/year figure which is confusingly in the same order of magnitude for xxxx. But very different uses!

The latter figure is only useful for comparing to your utility energy usage per year when trying to size a system (such as GTI) to offset your annual power consumption.
PS: I would never call the latter figure "irradiance". Far too confusing.

[Sunking]

Dave sorry to tell you your numbers are from outer space. If this is what you believe you are in for one hell of surprise when reality hits your bank account.