Chevy Volt

[FUEGO]

Since someone mentioned outdoor ones... it reminded me that I put two floods outside for my wife.... When you turn them on.... you can take a look at them and only a part of them are lit... the top half to 2/3rds is not producing any light... now, go out a few minutes later.... all is good..

If your outside flood lights are motion activated, make sure you have a light fixture that is CFL compatible. I didn't and I ended up burning out the circuitry using CFLs in a non-CFL compatible fixture. After burning out the circuitry, it would work intermittently, stay on for a few seconds, then maybe not work for a while.

I know home depot has cfl-compatible basic motion activated flood light fixtures for $20 or so, when the similar basic fixtures that are non-cfl compatible are just a few bucks cheaper.

The outside CFL's do take a few minutes to get to full brightness. However if the goal is illuminating the area where you are walking and shining a light on any car burglars that may want to smash your windows in, they perform acceptably, even with relatively low wattage bulbs (I think I'm running 1 90 watt equivalent).

 

[BigNick]

I'm having a hard time believing the GM numbers. 1 kilowatt is the same as 1.34 horsepower, so 8 kWh is equivalent to 10.72 horsepower for 1 hour.

Now the 8 kWh that goes into the battery isn't going to come back out at 100% efficiency, and the motor and drivetrain won't be 100% efficient either. But forgetting that for a moment, what GM is saying is that 10.72 horsepower is enough to propel the Volt at 40 mph, so after 1 hour it will have gone the rated 40 miles.

I suppose that's just about possible, although 10.72 horsepower seems awfully low to push such a big car through the air.

But how realistic is this scenario? I have to believe that in real life the gas engine is going to come on long before the 40 mile mark.

Thanks... I posted something similar and a couple of people said they thought I was too pessimistic.

I do not see people buying a vehicle with a range of only 40 miles. 100 or 150, maybe, provided that there's a fast-charge option - say, you drive into a "gas" station and they swap out your battery pack for a new one. But that introduces a whole new set of issues: storing those batteries, recharging them, ways to stop unscrupulous operators giving you half-charged batteries, etc.

My was to run cars "on electricity" would be to have them either burn hydrogen in Wankel engines, or use hydrogen fuel cells to run electric motors. The hydrogen would be produced by electrolysing water. Ideally that would be done by solar power, at the gas station itself - easier in San Diego than Vancouver, probably.

In my opinion, hydrogen offers a better chance of "getting there from here". Adding H2 - however it's produced or delivered to the gas station - will not require a change in the business model of 100,000+ gas stations, nor in the model of how we refuel our cars. On the other hand, batteries are a complete game changer - do you want to own such a massive consumable? (I saw one idea whereby you would own the car but lease the batteries for 3 or 4 years - then, having lost some of their storage capacity, they would get a second life in electrical storage heaters. I think the idea came from Renault, which would make sense as electricity in France is fairly cheap and low-carbon, being 70% nuclear-generated.)

 

[misanman]

How does running the heater on the Volt affect the range? We live in the upper midwest. I can imagine going outside to scrape the ice off the car with the temperature at 15 F. I suppose you could get "instant" heat from electrical resistance heating, but I'm not sure how long it would take to defrost everything with what sounds like the equivalent of a hair dryer.

 

[clifp]

I buy CFLs when they make economic and ergonomic sense. I'm sitting by one now, and I use them in my outdoor lights and a few other places. There are places I won't use them because it makes more sense to use the Edison light bulb. I use the right product for the right job. And when the govt provides subsidies, all it does is make that decision an artificial one. Just like these EVS, if someone wouldn't buy one with their own money, why should I give them the money to buy it? It doesn't change the equation.

If your answer is "to save energy", then I suggest that you define that goal, and look for solutions. I believe there are far better, more effective, faster acting, and more efficient ways to save energy, than artificially pricing some specific technologies.

BTW, our CFLs are using about twice as much energy as most people think. Look at the label and calculate the Volt-Amps. It will be about 2x the watts (Power Factor of 0.5). Our power meters charge by the Watt, because it was the only practical way to measure per household. But electrical plants (think coal) really have to generate Volt-Amps, the watt rating means nothing relative to the coal burned. If you are a big commercial place, they will check your power factor, and charge accordingly. Just can't do that home-by-home, but the end result is the same, CFLs are not even half as 'green' as claimed. Couple that with the fact they take more materials and more processing (which would be expected to take more energy), and the delta shrinks. Might even be negative for all I know. I wouldn't be surprised, looking at the box of dead ones and their fancy plastic packaging that I have for recycling.

-ERD50

Another disappointed CFL user. I replaced the bulb in the most heavily used places with CFL a few years ago, and for the other places as the old bulbs burned out. In my office it is entirely possible that lights are on 8 hrs x 300+ days year = 2,500 hrs/year so for a 10,000 hour life I shouldn't replace them more than every 4 years in fact they burn out in less than year.

Meanwhile my 2nd most used location bedroom probably has an hour a day of usage and the bulbs have never been replaced since I've lived here going on 5 years.

Now you tell me they don't save as much energy as the advertise.

Bloody hell, ERD next your going to tell me I can stop the sea levels from rising by unplugging my cell phone charger

 

[FUEGO]

Off the top of my head, I'm counting around 30 CFL bulbs in my house. I may have missed a few. I don't know how often I buy bulbs, but I don't think it is more than a 4 or 6 pack a year. So maybe an average lifespan of 6-7 years per bulb?

I think I'm getting a lot more life out of them versus incandescent bulbs.

I'm lazy and don't like changing light bulbs, so having to change them every few years versus say once a year is nice.

From a cost savings perspective, I figure a 60 watt equivalent is using 13 watts, or "saving" 47 watts. What is the 47 watts in savings worth? For me, 8 cents for a kilowatt hour for the electricity, plus maybe roughly another 4 cents per kilowatt hour because I have to cool down the house most of the year to offset heat production due to this hypothetical incandescent bulb. That means I'm saving around 0.56 cents per hour due to using one CFL. I get six packs of CFL's from walmart for somewhere around $6-8 versus a buck or two for a six pack of incandescents. Let's say a $1 marginal cost per bulb.

It takes around 177 hours of use to pay the roughly $1 marginal cost to buy a CFL instead of an incandescent. Virtually all of the CFL's I have bought in the last few years have lasted much longer than 177 hours. 177 hours = 1/2 hour a day for a year, or 1 hour a day for 6 months, 3 hours a day for 2 months, or 8 hours a day for 3 weeks. As you can see, in heavily used areas, CFLs can pay you back within weeks.

Of course I'm ignoring the externalities involved with producing CFLs and disposing of them properly. I'm not talking about saving the earth, I'm talking about saving money.

 

[Peter]

Thanks... I posted something similar and a couple of people said they thought I was too pessimistic.

Time will tell. I think the 40 mile figure is rather like quoted ranges for cordless phones, something that can be achieved under ideal conditions, but hardly ever in real life.

Peter

 

[ERD50]

I do not see people buying a vehicle with a range of only 40 miles. 100 or 150, maybe, provided that there's a fast-charge option - ...

Time will tell. I think the 40 mile figure is rather like quoted ranges for cordless phones, something that can be achieved under ideal conditions, but hardly ever in real life.

Peter

I'm not sure you are understanding what the 40 mile range number means with a Chevy Volt.

After a full charge, it will go (approximately) 40 miles on Electric Power alone. At that point, the Internal Combustion Engine automatically starts up, and generates enough electricity to keep the batteries from discharging any further. At that point, it is just like any other gasoline car, you can drive as far as you want by stopping and filling up on gas (300 mile total range between fill ups, IIRC).

It is a series hybrid (ICE >generator>Batteries>Electric Motor), different from a parallel hybrid Prius (ICE works in parallel with batteries/motor). For marketing differentiation, GM calls it an 'Extended Range Electric Vehicle' which I think is a good description.

The thinking is, most trips are under 40 miles, so you run primarily on EV, but you have the ICE/gasoline as 'backup' for longer trips. Makes some sense for the current state-of-the-art in batteries, but you carry the cost of the ICE. I think EVs won't gain wide acceptance until battery tech is such that you can get >200 miles on a charge at a price near the ICE model.

-ERD50

 

[samclem]

In my opinion, hydrogen offers a better chance of "getting there from here". Adding H2 - however it's produced or delivered to the gas station - will not require a change in the business model of 100,000+ gas stations, nor in the model of how we refuel our cars

Hydrogen has tons of problems. It's very difficult to transport and to store, producing it costs a lot (either in money or carbon). It briefs great and sounds cool, but it is the road to nowhere.

As a liquid fuel, methanol has a lot of positive aspects that are in line with your point--it could make use of much of the existing liquid-fuel infrastructure, it can be produced more cheaply and with less environmental/economic impact than ethanol. It can't totally replace petroleum, but it's a good adjunct to it.

The Hydrogen Hoax

 

[Peter]

I'm not sure you are understanding what the 40 mile range number means with a Chevy Volt.

After a full charge, it will go (approximately) 40 miles on Electric Power alone. At that point, the Internal Combustion Engine automatically starts up, and generates enough electricity to keep the batteries from discharging any further. At that point, it is just like any other gasoline car, you can drive as far as you want by stopping and filling up on gas (300 mile total range between fill ups, IIRC).

It is a series hybrid (ICE >generator>Batteries>Electric Motor), different from a parallel hybrid Prius (ICE works in parallel with batteries/motor). For marketing differentiation, GM calls it an 'Extended Range Electric Vehicle' which I think is a good description.

The thinking is, most trips are under 40 miles, so you run primarily on EV, but you have the ICE/gasoline as 'backup' for longer trips. Makes some sense for the current state-of-the-art in batteries, but you carry the cost of the ICE. I think EVs won't gain wide acceptance until battery tech is such that you can get >200 miles on a charge at a price near the ICE model.

-ERD50

Yes, I do understand all that.

I still think 40 miles with electric-only is the upper limit, and in real life driving it will be less than that.

But it's not a big deal. Really.

Peter



Peter

 

[eridanus]

BTW, our CFLs are using about twice as much energy as most people think. Look at the label and calculate the Volt-Amps. It will be about 2x the watts (Power Factor of 0.5). Our power meters charge by the Watt, because it was the only practical way to measure per household. But electrical plants (think coal) really have to generate Volt-Amps, the watt rating means nothing relative to the coal burned. If you are a big commercial place, they will check your power factor, and charge accordingly. Just can't do that home-by-home, but the end result is the same, CFLs are not even half as 'green' as claimed. Couple that with the fact they take more materials and more processing (which would be expected to take more energy), and the delta shrinks. Might even be negative for all I know. I wouldn't be surprised, looking at the box of dead ones and their fancy plastic packaging that I have for recycling.

-ERD50

Any "non real" power is not wasted. It goes back to the source. There might be increased load loss but it's inconsequential for a single family household. This is why large customers have PF charging -- due to heavy equipment, some customers send back a LOT of unused apparent power that causes load on the battery and lines.

Even if you assume that all of the unused power from a residence is lost, CFLs are still significantly more efficient than an incandescent.

You can measure this yourself:

A 60W incandescent requires 60VA (with PF of 1.0).
A 15W fluorescent requires 30VA (with PF of 0.5).


Let's ignore the fact that CFLs can have PFs greater than 0.5, leading to the question:

Why would anyone choose 60VA over 30VA?*


*Obviously, for dimmers or in a greenhouse or other niche applications.

 

[ERD50]

Any "non real" power is not wasted. It goes back to the source. There might be increased load loss but it's inconsequential for a single family household.

It's not inconsequential, unless you also want to categorize the savings from CFL as 'inconsequential' (which might be reasonable).

CFLs have a Power Factor around .5. They draw about 2X the current (watt-for-watt) that a load like an ILB does (Incandescent Light Bulb, I don't want to type that 10 times). 2X the current is 4X the power loss. The grid loses ~ 8% to distribution losses, so 4X is 32%, the delta being 24%. In relative terms (which is all that matters when you are comparing efficiency between two items), I don't see 24% as inconsequential.

And there still are other effects on the power company to generate that extra power. A quick google showed that Utilities charge their industrial users on a straight % basis if their PF is worse than baseline (.95 in the cases I saw). I don't think they could justify charging 20% more for a PF of .75 without a solid basis for it.

But that does mean I overstated it a bit, I said 100% additional energy used for PF of .5, while it would be closer to 50% additional. So thanks for bringing it up and forcing me to dig a bit deeper on this. Unlike some people, I appreciate being challenged as it forces me to learn and get my 'facts' straight.

CFLs are still significantly more efficient than an incandescent.

I never said they weren't. And as I said, I use them for some applications. But it is disingenuous to over-sell the environmental benefits, if a Fortune 100 company misstated some environmental benefit by 50%, people would be all over them (rightfully so). I'm not giving them, or the 'greenies' a pass. CFLs use ~ 50% more energy than most people think, and that just isn't right.

Maybe I'll google again, but in the past I never found a good number for the environmental cost of production and recycling over an ILB. Common sense tells me that more materials (look at how much more/thicker glass is in those things), more complexity (a circuit board), heavy base, and increased shipping and packaging are going to offset the environmental savings to some degree. How much, I do not know, but not zero.

-ERD50

 

[ERD50]

OK, this is from someone who seems to have good credentials, and she is saying 2X the energy at a 0.5 PF:

The Hidden Costs of CFLs | Will there be a price to pay for increased residential use of electronic ballasts with low power factor ratings?

.... says Doreen LeMay Madden, founder and principal designer for Lux Lighting Design, Belmont, Mass., and chairman of the Residence Lighting Design & Application for the Illuminating Engineering Society of North America (IESNA), New York. At a power factor rating of 0.5, a 15W screw-in CFL will actually use 30VA of energy

....

“The end-users don't fully realize that these low power factor compact fluorescents are not using the small amount of energy that they think,” LeMay Madden says. “They're using twice the amount of energy, plus they're causing distortion in the sine wave. The lower the power factor, the more distortion you get.”

This is an industry magazine, I don't think they can get away with the usual 'journalistic license' of the popular press.

Electrical Construction & Maintenance (EC&M) magazine is the technical authority for 130,000+ electrical professionals, including 80,000+ subscribers in electrical contracting firms (reaching all NECA and IEC member firms and ENR's top 50), 30,000+ subscribers in industrial plants and in commercial/ institutional facilities with 100+ employees (93% coverage of Fortune 1000 firms), and 20,000+ consulting electrical engineers.

-ERD50

 

[eridanus]

It's not inconsequential, unless you also want to categorize the savings from CFL as 'inconsequential' (which might be reasonable).

Yes, the power loss is inconsequential.

Apparent power is not (all) burned up or fed into a ground. It's re-phased and then re-used, possibly inside the house (your house is more than one circuit with CFLs on it, right?). If you measure the total power going into a house and the total power returning, you'll likely have a near-1 PF unless you're running a pump or a basement of UPSs.

Why do utilities charge industrial customers for a PF less than unity? Because heavy machinery has a very low PF, which feeds a lot of out-of-phase power back into the grid, which means that a very large inductor (or 10) has to be added just upstream of the industrial customer.

Finally, if you're really worried about this, get a CFL with a higher PF.

 

[ERD50]

If you measure the total power going into a house and the total power returning, ....

You seem to want to play both side of the fence on this one?

On one hand, you want to look at Power Factor in terms of total power to our house and say it is inconsequential. But if you look at the savings of a CFL compared to total power to our house, that would be inconsequential.

We have to keep it apples-to-apples. Yes, a CFL uses less energy than a comparable ILB to operate. Even though you may be billed for ~ 1/4 the energy, it is using about 1.5-2X what most people think (still 1/2 the energy, but let's not call it 1/4 then).

Do you really think that expert I quoted is wrong about this?

Finally, if you're really worried about this, get a CFL with a higher PF.

They cost more, probably take even more energy to make, and it will probably cost me more in operational costs (I'll assume the HPF models use more real watts than a LPF CFL). No thanks.

And it doesn't address my 'worries' anyhow. I'm worried when the public gets misinformation, esp about environmental issues as it often leads to counterproductive solutions. They should be honest with the consumer cost savings and the real energy savings of CFLs - do you really disagree with that?

-ERD50

 

[eridanus]

You seem to want to play both side of the fence on this one?

Quit quoting me out of context and it won't appear so.

Are you worried about PF or are you worried about actual power used? PF is NOT real power used. The "non-real" power is not lost in the ether (or the ground).

From the reactive power "used" by the CFL, subtract what's re-used in your house, and then you can figure out the line loss back to the substation (not to the coal plant). That will yield a more realistic number of how much power is lost. It's much, much, less than 50% for a cheap CFL.

Do you really think that expert I quoted is wrong about this?

The "expert" is obviously not an electrical engineer. The power not used for real work (i.e., light) goes back on the wire. It doesn't just disappear.



Edit:snarkiness removed

 

[Koolau]

Well, I'm totally confused, but that's not unusual. I don't understand electricity much beyond DC. I did always wonder how appliances "used up" the energy that went to them. And if they didn't use it all up, where did it go? And "phase": Fugidaboutdit. But it sounds like ERD50 and eridanus understand the "ins and outs". Thanks for the treatise on the subject. This may be food for further thought and research on my part. Interesting stuff

 

[ls99]

Thanks for the discussion, Eridanus and ERD50.

About ten years ago spent a lot of time on correcting for power factor of less than 1, mostly for motors and transformes.

In that vein can always work out the formula and add a correcting capacitor or inductor on back side of the light socket, so the apparent power will recycle to the CFL. Don't know if current in CFLs it is lagging or leading. Chances are the the value of the cap or coil and the time required to calculate, then actually do the work is a lot more hassle than the value of inefficiency corrected for.

IIRC one should not attempt to actually correct to 1. Can't remember the reason. Something about resonance, though that seemed to only apply to inductive devices like motors..

 

[eridanus]

Thanks for the discussion, Eridanus and ERD50.

About ten years ago spent a lot of time on correcting for power factor of less than 1, mostly for motors and transformes.

In that vein can always work out the formula and add a correcting capacitor or inductor on back side of the light socket, so the apparent power will recycle to the CFL. Don't know if current in CFLs it is lagging or leading. Chances are the the value of the cap or coil and the time required to calculate, then actually do the work is a lot more hassle than the value of inefficiency corrected for.

IIRC one should not attempt to actually correct to 1. Can't remember the reason. Something about resonance, though that seemed to only apply to inductive devices like motors..

Harmonic distortion?

I think a CFL needs a capacitor. Adding some caps and coils might actually zero out the power measured by the meter. For example, if you take the "real" power and correct the reactive power and send it back...voila! No power used.


And thanks for mentioning inductive motors. They'd need large capacitors to correct the electricity, not inductors as I wrote.

 

[Pete]

GM should've been way ahead on this technology with their EV1 start. Too bad for them. GM is selling, not leasing them this time. It's gonna be much harder to put this genie back into the bottle.

Most people hate and distrust the oil lobby and industry in general . The proper handling of media and commercial could get people to spend a little more just to screw them over.

The gov't has been subsidizing oil for almost 100 years. Why not electric?

We've talked about this before here. My neighbor had an EV1. I was able to do a very good study on it, while he had it. Except for the fact it had a special electric plug in, it was the best car I've ever seen.

 

[clifp]

Well, I'm totally confused, but that's not unusual.

Don't feel bad I have an EE degree and I only vaguely understand the discussion. I focused on computers not power systems and it was 30 years ago, what can I say.

For a good layperson discussion, the wiki entry on CFLs was educational.

A few highlights from Wiki article.

The average rated life of a CFL is between 8 and 15 times that of incandescents.[11] CFLs typically have a rated lifespan of between 6,000 and 15,000 hours, whereas incandescent lamps are usually manufactured to have a lifespan of 750 hours or 1,000 hours.[12][13][14] Some incandescent bulbs with long lifetime ratings have been able to trade efficiency for lifespan, slightly reducing light output to significantly improve the rated life. The lifetime of any lamp depends on many factors including operating voltage, manufacturing defects, exposure to voltage spikes, mechanical shock, frequency of cycling on and off, lamp orientation, and ambient operating temperature, among other factors. The life of a CFL is significantly shorter if it is turned on and off frequently. In the case of a 5-minute on/off cycle the lifespan of a CFL can be reduced to "close to that of incandescent light bulbs".[15] The US Energy Star program suggests that fluorescent lamps be left on when leaving a room for less than 15 minutes to mitigate this problem.

The 5 minute on/off cycle certainly explains the bathroom CFL problem discussed earlier, although it doesn't explain my problem of early burn out for my long running lights in my office.

I went and looked at fine print of my package of CFLs. I seems despite the claim of 10,000 hours on the package the actual warranty is considerably less. A two year warranty for normal 3 hr/day residential usage or 1 year warranty for commercial usage and if you call the 800 number they will in theory replace the bulbs. (No clue if you have to pay for shipping.) This is equal to a 2,000 hour lifetime better than IFL but no where close to the claims but perfectly consistent with my experience.

As always for controversial subjects I found the wiki discussion page to be illuminating (sorry). There was support for both ERD50 and Eridanus positions on power factor. Also the difference in quality of Chinese manufactured light bulb was mentioned and sure enough my CFLs were made in China.

Overall both the Volt/Electric Vehicle and the CFL discussion are providing further evidence to a pet peeve of mine. "Putting the green label on something enables you to make exaggerated claims which seem to get a pass from any type of government regulators or industry watch dogs"

Now I am all for encouraging energy efficiency (since it is the cheapest form of alternative energy) and electrifying vehicles is also a very good thing, IMO I am even willing to subsidize this trend, because I believe we really need to move from an oil based economy.

However, I am not willing to suspend the normal rules about false advertising and green product are notorious for over promising and under delivery. If this continues I fear that there is going to be a huge backlash against green products by the American public.

As P.T. Barnum said you can fool some of the people all of the time, and all of the people some of the time, but you can't fool all of the people all of the time.

 

[M Paquette]

Oh, boy. Power factor and CFLs. I'm a little late to the conversation, but there is some stale data that stood out here.

Power factor refers to the odd behavior where the voltage and current being drawn by a load get out of phase. Big inductive loads like motors and fluorescent fixture ballasts produce a lagging power factor, and big capacitive loads produce a leading power factor.

Because of power factor, the power measured in watts for a device may be lower than the simple product of volts times amperes, volt-amps or VA. The VA load is important in sizing the conductors, transformers, and other components, as the current being drawn is the limiting factor, rather than total power. A high current draw uses more transmission line capacity, without regard to wattage. That's why power companies charge extra to commercial consumers with poor power factors, and why you'll sometimes see huge capacitors in private substations to correct the power factor closer to 1.0.

GS-5 compliant class A compact fluorescent bulbs are supposed to have a power factor greater than 0.9, leading or lagging. These meet code requirements for sale in most of Europe and Asia.

Semi-resonant (inductor + capacitor) and electronic ballasts also tend to have a power factor very close to 1.0. For residential lighting I'd look for lamps with a 'high frequency electronic ballast', as these will have a PF close to 1.0, and will be fast starting and free of that annoying 60/120 Hz flicker. (Some people aren't bothered by it, but I notice it. Ceiling fans...)

 

[HFWR]

Don't feel bad I have an EE degree and I only vaguely understand the discussion. I focused on computers not power systems and it was 30 years ago, what can I say.

Yeah, AC made my head hurt... Ditto on the 30 years, also.

The 5 minute on/off cycle certainly explains the bathroom CFL problem discussed earlier, although it doesn't explain my problem of early burn out for my long running lights in my office.

The only CFL to fail in my house was one bathroom light. All others 3-ish years old now. Granted, I'm likely not a typical user. I use LED lights in some locations, for just enough light to get around without tripping.

Now I am all for encouraging energy efficiency (since it is the cheapest form of alternative energy) and electrifying vehicles is also a very good thing, IMO I am even willing to subsidize this trend, because I believe we really need to move from an oil based economy.

I agree with this in principle, though I have many of the same types of doubts as samclem, ERD50, and others, that often the pseudoscience of "green" is surpassed only by diet plans, or possibly annuity salespersons...

However, I am not willing to suspend the normal rules about false advertising and green product are notorious for over promising and under delivery. If this continues I fear that there is going to be a huge backlash against green products by the American public.

Not fair to single out "green" here, though; almost all advertising is this way.

 

[ERD50]

Wow, lots of posts since I was out doing mundane mechanical stuff like cutting the grass, fixing the mower, finishing cutting the grass, eating dinner... Back to the subject at hand...

Edit:snarkiness removed

No worries (whatever you said), I'm enjoying the exchange, and I don't have thin skin when it comes to this stuff . Carry on, but don't get in trouble with the mods.

I had a chance to google some things, and now I think I see where theory is meeting the real world.

Like a few others, it's been about 35 years since I was nodding off in front of a blackboard filled with Power Factor correction formulas. Never used it even once in my whole career, so applying this to a real world application is kinda interesting in that geeky kinda way.

So of course, eridanus is correct when he says the real power is the Watts, not the VA. And as others have found, there is some conflicting info out there on the application of this subject - so here is where the theory and practice meet (from what I've re-learned so far):

As we've discussed, a device with a PF of .5 (CFL) draws 2X the current of an equal wattage device with a PF of 1 (ILB). And 2X the current will have 4X the losses in the distribution system.

What I thought was, that the generator at the power station had to produce Volt-Amps. Well, it does, but as far as I can tell, the Horsepower required to turn it is based on the real power (Watts), not the Volt-Amps. So in theory, (except for compensating for the increased distribution losses), a generator shouldn't burn any more coal producing power for a device with PF1 or PF 0.5 of equal wattage (except for the fact that a generator that can handle higher current will be bigger and heavier and have more friction). However....

Remember those distribution loses? 8% on average for the grid, so the PF 0.5 takes those loses to 4x8=32%, so 24% additional loss. And generators are not 100% efficient either, maybe 90% (no time to google it now). I'd assume a big part of that inefficiency is loss due to current. So the increased current from a PF 0.5 will also increase the losses in the generator. If those losses are 5%, they would also increase to 4X at PF 0.5, to 20%. Add that to the 24% and we are in the ballpark of 1.5X energy consumption for a CFL than the watts rating would indicate.

If someone can put a closer estimate to those numbers, please do. But I fall back to my real world gut check - in the examples I saw, the Utilities bill on a near linear scale, charging 20% more for a .75 PF (.25 away from the ideal of 1.0), and there must be a reason for that.

-ERD50

 

[clifp]

I agree with this in principle, though I have many of the same types sof doubts as dsmclem, ERD50, and others, that often the pseudoscience of "green" is surpassed only by diet plans, or possibly annuity salespersons...



Not fair to single out "green" here, though; almost all advertising is this way.

Actually I do think it is fair to single "green" products out, they are really some of the worse offenders. You can't advertise a car gets 100 MPG by looking at the amount of fuel used starting at the top of Pike Peak and than measuring how much fuel is left at the bottom of the mountain you have to use an EPA estimate. Now your mileage my vary etc. but the EPA number is generally with 10-20%. They don't allow the gimmicks I've seen in promoting the electric vehicles that ignore the oil/coal used to generate the electricity.

The roof mounted windmill or solar panels that claim they can power your whole house, when in reality in most situation they'll only deliver 1/3 of your power needs. CFL that claim 10,000-15,000 hours but only end up lasting for 2,000 hours. The windmill or solar farms that advertise that they'll provide power for 20,000 homes but neglect to tell you that it is really for 20,000 studio condos.

The Energy Star Stickers which automatically approved by the EPA with no verification. There was a funny but sad story how the General Account office made up fictitious products and submitted them to the Energy Star Program and almost all of them were approved.


Sure a bit of puffery and exaggeration are part of advertising, but believe it or not, the FTC, FDA, and even the networks and newspapers actually monitor this stuff. If you advertise that your food product or supplement provides a health benefit, it better be damn well be documented and backed by peer reviewed journals or the FDA will create a world of trouble for you.

I was pleasantly surprised when the big three TV network ads demanded proof about specific performance claims that Intel made for its microprocessor before they would allow our commercials to be run on their networks. Same thing was true with Wall St. Journal.

In Germany if you claim that your product is superior to a competitors you need a extensive documentation, because this type of advertising is frowned upon on (or at least it was a decade ago).

I simply don't see anywhere near the level of scrutiny about green products that I see for the rest of stuff we buy.

 

[ERD50]

Ahhh - I forgot this was the Chevy Volt thread, not the CFL thread. Soooo, to bring this back to the OP subject, I wonder what the PF of the charger for the Chevy Volt is?

And an odd coincidence, as I was out driving to pick up parts for my mower, NPR had some news items on the Volt. Turns out it misses qualifying for the California laws for the 'special' HOV - car-pool/hybrid lanes by just a smidgen. So the govt will give you $7,500 for a vehicle that doesn't qualify for the HOV lanes on govt highways - some crazy stuff going on.

You know, I might feel slightly better about the $7,500 subsidy if someone, anyone, could provide the background on it. Was there any sort of actual numeric justification made? No matter how hand-waving it was, I wonder if there was anything at all? How do you calculate, even extremely approximately the ROI on a $7,500 subsidy? Why not a 100% subsidy, let's really get those EVs out there! After all, it will take 12 years to get most of the current cars off the road, need to start soon!

-ERD50