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  • khanh dam
    replied
    dont' try to justify your assumptions, just move on, you didn't call BS on anything. you assumed something incorrectly and then make a big deal out of nothing.

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  • J.P.M.
    replied
    Originally posted by khanh dam View Post
    que up the hyperbole band.
    With statements from you saying volcano goddesses don't have telescopes seems to me that statement above is kind of like the pot calling the kettle black.

    Seems to me that statements such as "If only the natives in Hawaii would use the geothermal sources under their feet they would have reliable electricity" infer that doing so would meet all their energy needs. That's the stuff half truth and misleading by inference. The rest of the story that takes the wind out of the original statement only shows up after I called B.S. on it.

    Of course the plant is being reopened. But the very idea that it was down due to an eruption says a lot about reliability, which was one of my points.

    Given the definition of hyperbole, with respect to it not meant to be taken seriously anyway, I've not produced any in this thread. If I did, you'd see the sarcastic font used.

    Leave a comment:


  • SunEagle
    replied
    Originally posted by khanh dam View Post
    no one said the entire island could be powered by geothermal either., it is not an extraordinary claim either, it is a real world tested system that worked in the past and will continue to work
    I believe a combination of thermal, solar, wind and possibly wave energy would provide close to 100% of the needed power for an island. You still have to include load shed or load reduction control for those weird peak usage times when enough renewable energy is not available to meet the customer needs.

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  • khanh dam
    replied
    no one said the entire island could be powered by geothermal either., it is not an extraordinary claim either, it is a real world tested system that worked in the past and will continue to work

    Leave a comment:


  • khanh dam
    replied
    que up the hyperbole band. Here is what I know, before the volcanoe erupted in 2018 the geothermal plant produced 30% of the big islands' electricity needs. They are reopening it not because they are tree huggers, but because it makes economic sense. I do not need to be a power plant guru to figure out the obvious. it makes economic sense to use a huge power source rather than import diesel to an island in the middle of the pacific.

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  • J.P.M.
    replied
    Originally posted by khanh dam View Post
    no also do not have evidence that Pele the volcanoe goddess doesn't like telescopes or renewable energy. It is a no brainer which is why the plant is opening back up. Why import diesel fule when you are litterally sitting on a huge energy source.
    How huge and how do you know or what information can you provide to back up your claims besides mocking sarcasm ? Extraordinary claims need extraordinary evidence.

    How much do you know about the resource, the load and how to best interface the two ?

    Given what I think I might know about power generation, seems like powering HI entirely on geothermal as you seem to be implying is more like a no brainer for the ignorant, but maybe my career in power and process engineering was no more than an exercise in futility.

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  • khanh dam
    replied
    no also do not have evidence that Pele the volcanoe goddess doesn't like telescopes or renewable energy. It is a no brainer which is why the plant is opening back up. Why import diesel fule when you are litterally sitting on a huge energy source.

    Leave a comment:


  • J.P.M.
    replied
    Originally posted by khanh dam View Post
    If only the natives in Hawaii would use the geothermal resources under their feet they would have reliable independent electricity. Geothermal plant was shut down last year, hopefully it will reopen on schedule in 2020. In other areas concentrated solar should be in use. HI. had ONE trial concentrated solar plant, from what I have googled it never produced electricity for the general public, weird. instead HI is using https://recsolar.com/all-case-studies/waianae-solar/
    huge PV plants, I thought Concentrated solar was more efficient? and one can store the extra energy in heat storage. of course much MUCH more expensive to get up and running and with a volcanoe potentially wiping it out easily, I guess that is why PV is more common.
    You have solid #'s to back that geothermal statement up, right ?

    Seems like if geothermal could be done in ways safe, reliable, practical, and cost effective it would be a no brainer in HI.

    BTW, I've designed boilers for geothermal plants down around the Salton Sea. Not easy service. Not always as reliable as you might think either.

    Leave a comment:


  • jflorey2
    replied
    Originally posted by Harok375 View Post
    So. if I'm looking at this right, it looks like 10 years to pay it off?
    I've run the numbers for that myself and they tend to not make sense.

    There is one exception, and that's if you have an EV - because then you can switch to EV-TOU-5 and effectively pay for all your power at the 9 cent/kwhr rate. I have a friend of mine who has cut his power bill by about 70% without using solar, just enough storage to zero out his consumption outside the "cheap" window. (He also charges his car at that time.) For him it's a no brainer because he's using a 6kwhr system that cost him $2000 using second life EV batteries. With commercial gear it's harder to make it work out, but the higher value of solar generation can really help there.)

    Leave a comment:


  • Harok375
    replied
    Originally posted by NEOH View Post

    I am not familiar with your Time-Of-Use periods, so ...
    During what off-peak time period ( begin & end ) will you charge the Battery Bank?
    During what on-peak time period ( begin & end ) will you discharge the Battery Bank?

    I will assume ... Peak-Time is from 1:00pm - 7:00pm
    Do you think, you can actually re-charge the battery bank, starting at sunrise, and ending at 1:00pm ?
    Is it possible to recharge a 50% discharged battery bank, back up to 100%, from 8:00 am by 1:00pm = 5 Hours?
    I sincerely doubt it.

    You can discharge the battery bank from 100%, down to 50%, from 1:00pm until 7:00pm, in 6 hours.
    But then you are pushing a total of 48 AMPS ( PV + Battery ) back into the Grid.
    48 Amps is way too much for a typical 200 amp Main Panel = maybe a Supply-Side Tap is required?

    Have you verified with your Electric Company, in writing, that they will CREDIT 100% of your Peak-Time over-production at $0.38/kWhr ?
    And this is guaranteed for how many years?

    https://www.greenconvergence.com/blo...ll-cut-benefi/

    In central California, currently, we have the option of selecting a 3-8 peak, where rates are 27/29 in winter, and 33/41 in summer, or a 4-9 peak, where rates are 23/25 and 28/38.

    Interestingly enough, we're currently on tiered and pay 22/28 year round. So a rate hike for going solar and saving the world, lol.

    Our roof faces a little to the east - 150 degrees, if you believe the iPhone compass - and so the readout I got from the first geek predicts a decreasing level of PV output by the time we get into peak rate times. Surely by 4, not much would be going on.

    But as noted, I've pretty much abandoned this idea of it making financial sense and would incorporate it ONLY as a power outage backup, with excess PV production and perhaps a little battery going back to the grid, with a small generator "somehow" automatically started - our rv generator has electric start - that would be set to start up and charge batteries when battery voltage drops to some as yet to be determined level. OR... no battery at all and get a regular standby/natural gas generator.

    Edit- nothing in writing cuz I'm still researching.
    Last edited by Harok375; 08-19-2019, 01:05 PM.

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  • NEOH
    replied
    Originally posted by Harok375 View Post
    Well, here it goes.

    Wife and I are finally making the jump to installing solar ( mainly we want the 30% credit in Cali before it runs out and/or diminishes ) and I'm trying to figure out if installing batteries ( cuz I'll get 30% PLUS $250/kWh rebate if I do it ) makes any sense at all.

    Some background: We will be on a grid tie system. Batteries - if purchased - will be used simply as storage from pv system during off peak to sell back to the grid during on peak. There is no plan to try and turn the battery system into a blackout system. I have plans to install a generator for that down the road.

    ...

    35 (kWh) x .26 (.38-.12) x 5 (days per week) x 26 (weeks in 6 months ) = $1183 net.

    This being the case, why would anyone get batteries?
    I am not familiar with your Time-Of-Use periods, so ...
    During what off-peak time period ( begin & end ) will you charge the Battery Bank?
    During what on-peak time period ( begin & end ) will you discharge the Battery Bank?

    I will assume ... Peak-Time is from 1:00pm - 7:00pm
    Do you think, you can actually re-charge the battery bank, starting at sunrise, and ending at 1:00pm ?
    Is it possible to recharge a 50% discharged battery bank, back up to 100%, from 8:00 am by 1:00pm = 5 Hours?
    I sincerely doubt it.

    You can discharge the battery bank from 100%, down to 50%, from 1:00pm until 7:00pm, in 6 hours.
    But then you are pushing a total of 48 AMPS ( PV + Battery ) back into the Grid.
    48 Amps is way too much for a typical 200 amp Main Panel = maybe a Supply-Side Tap is required?

    Have you verified with your Electric Company, in writing, that they will CREDIT 100% of your Peak-Time over-production at $0.38/kWhr ?
    And this is guaranteed for how many years?

    https://www.greenconvergence.com/blo...ll-cut-benefi/
    Last edited by NEOH; 08-18-2019, 03:39 PM.

    Leave a comment:


  • Ampster
    replied
    Originally posted by J.P.M. View Post

    Ever hear of lying by omission ?
    Exactly. That is why it is important to become informed before asking a question like that of a salesperson. After the fact, it is much easier to blame a salesperson than reflect on how one could have become better informed or tested the answer with a source that is more reliable. Trust but verify is a concept, and the important part is the verify part.
    Last edited by Ampster; 08-19-2019, 01:06 PM.

    Leave a comment:


  • J.P.M.
    replied
    Originally posted by harok375 View Post


    yep. It's like anything in life.

    You've got to educate yourself and be your own advocate cuz no one's gonna be on your side where there's a sale involved.

    My favorite pet peeve is when a doctor or hospital sells you something that you may not really need cuz "you've got great insurance."

    yeah i've got great insurance, but it doesn't pay 100% of that unnecessary mri you say i need. I'm having an asthma event, not a heart attack. So i'm paying 20% of that $2000 mri bill. So no thanks, do your job.
    fwiw, +1.

    Leave a comment:


  • Harok375
    replied
    Originally posted by J.P.M. View Post

    Ever hear of lying by omission ?

    Yep. It's like anything in life.

    You've got to educate yourself and be your own advocate cuz no one's gonna be on your side where there's a sale involved.

    My favorite pet peeve is when a doctor or hospital sells you something that you may not really need cuz "you've got great insurance."

    Yeah I've got great insurance, but it doesn't pay 100% of that unnecessary MRI you say I need. I'm having an asthma event, not a heart attack. So i'm paying 20% of that $2000 MRI bill. So no thanks, do your job.

    Leave a comment:


  • Harok375
    replied
    Originally posted by Ampster View Post
    Salesperson dishonest or just not complete?

    Theoretically the answer is yes, but it is uneconomical and permission from the utility is not likely. There are many things about utility rates and rules that defy logic.
    As to your question it depends on the rates and whether you can use the tax credit economically.

    Yeah at this point, it's pretty obvious that having batteries makes absolutely zero economic sense.

    This whole discussion raises some odd questions for me:
    1- I understand the problems that PG&E is/can have with the whole duck curve thing, and therefore how PV systems incorporating batteries that are charged by the PV system can be an advantage for them, cuz they won't have to PAY to export power.
    2- A PV system with batteries can help avoid starting peaker plants and thus CO2 production.

    Q#! - why aren't power companies more behind this? Presumably it's about profitability?
    Q#2- since CO2 is such a political hot button, why isn't the legislature doing more to make the power companies help make homeowners see a financial advantage? I personally think that most homeowners would incorporate batteries even if it was only a break even proposition. Presumably it's about not losing campaign contributions?

    For us, the only consideration for batteries at this point is for a power outage backup situation where we just skip all the crap with trying to get a tax credit for overpriced batteries, etc and just either:

    1- use a standard stand by generator from Generac or whoever that kicks on automatically during an outage. The downside, I believe, will be the slight delay to power up and the resulting blinking clocks, lol. Prolly cost around $6-7k installed.
    2- use the aforementioned rv generator and somethimg like a Nissan Leaf DIY battery pack from Tech Direct on Ebay for around $1200. Hopefully, no blinking clocks and no A/C starting issues if I were to use a soft start circuit.

    Still lots to think about.....

    Leave a comment:

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