Energy storage, cheap and low tech.

[MossRoad]

I doubt the end to end efficiency claim. Im thinking that the losses are actually 14% for both the up conversion and the down conversion. ie, 86% of energy put in is stored at hilltop - and 86% of that can be gotten back. ... ~74% overall

So you'd only be getting 74% interest on your free money instead of 100%. Sounds like a good deal. :laughing:

 

[orezok]

And no one has done that yet.

And if they do, from some quick web searches, to produce 50KW it has to run at 5000rpm. Typical Prius owners report their engines are running anywhere between 1000 and 2500 RPM at 70 MPH. So 5000 RPM is like running your Prius at 90+ MPH. Who would want their car sitting in their driveway running at 5000rpm for hours or days at a time? Its only got an 11 gallon tank. It would drain it 3-4 times a day and it would be the equivalent of running at 90+ MPH for 24 hours, or about 2000 miles! Who's going to want to put 2000 miles of hard wear and tear on their car each day and suck down 40+ gallons of fuel?

I respect your opinion and many informative posts, but several things need to be corrected.

First - I never mentioned a "kit" in my posts. You must be confusing me with other posts.

Second - I don't know where you got your information that the Prius needed to run at 5,000 RPM to produce it's maximum output. Here is a chart for the early version of the Prius (30kW) that clearly indicates that the maximum output occurs between 940 and 2,000 RPM, significantly lower RPM than a typical generator. In fact at 5,000 RPM the output drops off.

 

[SPYDERLK]

And no one has done that yet.

And if they do, from some quick web searches, to produce 50KW it has to run at 5000rpm. Typical Prius owners report their engines are running anywhere between 1000 and 2500 RPM at 70 MPH. So 5000 RPM is like running your Prius at 90+ MPH. Who would want their car sitting in their driveway running at 5000rpm for hours or days at a time? Its only got an 11 gallon tank. It would drain it 3-4 times a day and it would be the equivalent of running at 90+ MPH for 24 hours, or about 2000 miles! Who's going to want to put 2000 miles of hard wear and tear on their car each day and suck down 40+ gallons of fuel?

You only use as much engine HP as is needed to produce the power the house needs. The engine would automatically throttle up and down to meet the power demand. Like an inverter generator set does.

 

[SPYDERLK]

I respect your opinion and many informative posts, but several things need to be corrected.

First - I never mentioned a "kit" in my posts. You must be confusing me with other posts.

Second - I don't know where you got your information that the Prius needed to run at 5,000 RPM to produce it's maximum output. Here is a chart for the early version of the Prius (30kW) that clearly indicates that the maximum output occurs between 940 and 2,000 RPM, significantly lower RPM than a typical generator. In fact at 5,000 RPM the output drops off.

Those are motor/gen speeds. Not engine speeds

 

[SPYDERLK]

So you'd only be getting 74% interest on your free money instead of 100%. Sounds like a good deal. :laughing:

I think you need to include a few other things in your cost vs benefit thought process.

 

[orezok]

Those are motor/gen speeds. Not engine speeds

The Prius uses a power split device that automatically adjusts the speed of the motor/generator to match the load independent of engine speed. If you only needed 10kW to run your application, it may well accomplish that at high idle.

 

[SPYDERLK]

And no one has done that yet.

And if they do, from some quick web searches, to produce 50KW it has to run at 5000rpm. Typical Prius owners report their engines are running anywhere between 1000 and 2500 RPM at 70 MPH. So 5000 RPM is like running your Prius at 90+ MPH. Who would want their car sitting in their driveway running at 5000rpm for hours or days at a time? Its only got an 11 gallon tank. It would drain it 3-4 times a day and it would be the equivalent of running at 90+ MPH for 24 hours, or about 2000 miles! Who's going to want to put 2000 miles of hard wear and tear on their car each day and suck down 40+ gallons of fuel?

You only use as much engine HP as is needed to produce the power the house needs. The engine would automatically throttle up and down to meet the power demand. Like an inverter generator set does.

I respect your opinion and many informative posts, but several things need to be corrected.

First - I never mentioned a "kit" in my posts. You must be confusing me with other posts.

Second - I don't know where you got your information that the Prius needed to run at 5,000 RPM to produce it's maximum output. Here is a chart for the early version of the Prius (30kW) that clearly indicates that the maximum output occurs between 940 and 2,000 RPM, significantly lower RPM than a typical generator. In fact at 5,000 RPM the output drops off.

Those are motor/gen speeds. Not engine speeds

The Prius uses a power split device that automatically adjusts the speed of the motor/generator to match the load independent of engine speed. If you only needed 10kW to run your application, it may well accomplish that at high idle.

Pls integrate points already made; otherwise you essentially are going to shift the subject

,,,,,,,The point being made for 5000rpm was refuted as only applicable to 50kW demand. And the rpm of the engine is not the motor/gen rpm, but that of most efficient throttle and speed needed to get enuf power from the motor/gen.

 

[buickanddeere]

I doubt the end to end efficiency claim. Im thinking that the losses are actually 14% for both the up conversion and the down conversion. ie, 86% of energy put in is stored at hilltop - and 86% of that can be gotten back. ... ~74% overall

74% is rather optimistic. Total Mw/hrs of stored energy is too low to be of any use.

 

[buickanddeere]

Stacking losses there.

 

[KennyG]

So you'd only be getting 74% interest on your free money instead of 100%. Sounds like a good deal. :laughing:

I think the way to look at it is getting 74% OF your money back, not 74% Interest ON your money.