X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • #16
    Originally posted by PNPmacnab View Post
    "I'd respectfully suggest better sizing methods during design,"

    Got a formula? Or is this like pornography, "I know it when I see it"?
    No, or at least not just one. Just a few observations and thoughts on how to reduce an electric bill.

    But since you seem to be curious, IMO only, most folks would come out ahead by spending most or all initial time, effort and resources educating themselves about energy and how it's used. Usually, from what I've seen, after getting real information - not from those with skin in the game - the more successful methods begin with some idea of defining the problem and setting goals, and then exploring ways to achieve those goals.

    What I've usually seen for the better of than half of my day/day life since getting involved in energy matters (and what I read here as well a lot of the time) is what often looks like some headlong near panic fleeing from self induced high electric bills that address the symptoms (the high bills) and not the causes of those bills - those causes most often having their origins in ignorance about the ways energy is used and ways to reduce that use.

    Then, unscrupulous peddlers use that ignorance to separate the unknowing from their money and sometimes, or maybe even often, make matters worse.

    Call it arrogant, condescending or whatever as you wish, NOMB or care, but my semi educated guess is that if more folks knew some of want I think I might know about the subject, their bills would be a lot less, there'd be a lot fewer residential PV systems, and those that did exist would be a lot smaller and better designed.

    So, formula - no. Observation and opinion - yes : Ignorance is the lock on the door leading to the goal of reduced bills. Real education is the key to more cost effective solutions, many of which have nothing to do with solar energy which, because, in reality, PV is about the most cost INeffective way to reduce an electric bill, and therefore, for many, even most situations, ought to be one if the last measures taken, if at all.

    Take what you want of the above. Scrap the rest.

    Comment


    • #17
      Originally posted by J.P.M. View Post

      No, or at least not just one. Just a few observations and thoughts on how to reduce an electric bill.

      But since you seem to be curious, IMO only, most folks would come out ahead by spending most or all initial time, effort and resources educating themselves about energy and how it's used. Usually, from what I've seen, after getting real information - not from those with skin in the game - the more successful methods begin with some idea of defining the problem and setting goals, and then exploring ways to achieve those goals.

      What I've usually seen for the better of than half of my day/day life since getting involved in energy matters (and what I read here as well a lot of the time) is what often looks like some headlong near panic fleeing from self induced high electric bills that address the symptoms (the high bills) and not the causes of those bills - those causes most often having their origins in ignorance about the ways energy is used and ways to reduce that use.

      Then, unscrupulous peddlers use that ignorance to separate the unknowing from their money and sometimes, or maybe even often, make matters worse.

      Call it arrogant, condescending or whatever as you wish, NOMB or care, but my semi educated guess is that if more folks knew some of want I think I might know about the subject, their bills would be a lot less, there'd be a lot fewer residential PV systems, and those that did exist would be a lot smaller and better designed.

      So, formula - no. Observation and opinion - yes : Ignorance is the lock on the door leading to the goal of reduced bills. Real education is the key to more cost effective solutions, many of which have nothing to do with solar energy which, because, in reality, PV is about the most cost INeffective way to reduce an electric bill, and therefore, for many, even most situations, ought to be one if the last measures taken, if at all.

      Take what you want of the above. Scrap the rest.
      +1. Good observations.

      Comment


      • #18
        Originally posted by DanS26 View Post
        I have four sources of heat in my house.....wood, propane, grid electricity and PV power. I can pick and choose which heat source I want to use. To make my choice I weigh in a variety of factors.....cost, convenience, efficiency and comfort.

        Wood at $65 per rick delivered is least costly at ~$5.20 per MMBtu is comfortable but it is very inconvenient and messy.

        Propane at $0.879 per gallon (yes that is actual price I paid for summer fill up) is ~$10.43 per MMBtu is comfortable, convenient and, at least for now, somewhat affordable.

        Grid electricity at $0.105 per kWh is ~$30.76 per MMBtu is comfortable and convenient but is very expensive to use as heat.

        PV power at $0.03 per kWh (yes that is my actual production cost) is ~$8.82 per MMBtu is comfortable but somewhat inconvenient since I only heat two rooms with it through my ETS systems. But in those two rooms it is very efficient and cost effective.

        So there you go....I use my ETS systems and supplement with propane for heat because at my age I like comfort and convenience. Its not rocket science.
        Not doubting your veracity, but I'd be interested to know the method you used to get the PV cost/MM BTU that low. That seems pretty close to or even less than what some POCOs call their avoided cost of energy.

        The last time I calc'd it, my LCOE was about $0.18/kWh for the electricity generated from my array on a 12 yr. life cycle.
        Last edited by J.P.M.; 01-09-2017, 01:56 PM.

        Comment


        • #19
          Originally posted by J.P.M. View Post

          Not doubting your veracity, but I'd be interested to know the method you used to get the PV cost/MM BTU that low. That seems pretty close to or even less than what some POCOs call their avoided cost of energy.

          The last time I calc'd it, my LCOE was about $0.18/kWh for the electricity generated from my array on a 12 yr. life cycle.
          I would expect the labor was free or DIY and the panels were purchased at wholesale prices.

          Comment


          • #20
            Originally posted by J.P.M. View Post

            Not doubting your veracity, but I'd be interested to know the method you used to get the PV cost/MM BTU that low. That seems pretty close to or even less than what some POCOs call their avoided cost of energy.

            The last time I calc'd it, my LCOE was about $0.18/kWh for the electricity generated from my array on a 12 yr. life cycle.
            First off I designed and constructed my grid tied solar system on my own time, thus I do not have any outside labor in the calculation. I sourced as many parts as I could locally getting the contractors discount (since they know and trust me). I over sized the system to twice my annual usage thus getting something like an economy of scale (like pallet pricing). I'm on a "net billing" plan so I could oversize (within reason up to 25 kW AC) without penalty. I added the cost of a couple of inverters in about year 12. I do my own maintenance and I took the 30% tax credit on my sunk costs. There's the numerator.


            For the denominator I used PVWatts production estimate, which was adjusted to my actual system performance, over a 25 year system life derated at 0.71% per year over that life span.

            The actual production cost based on the above is $0.0301086 per kWh.

            Hoosier Energy that produces energy for my local REMC produces at $0.025 per kWh. They sell that production, including distribution and demand charges at $0.065 per kWh to my REMC. My REMC turns around and sells it to me at $0.105 per kWh retail. If I produce excess my REMC will buy it from me at $0.065 wholesale. I think it is a sweet deal.

            When I was in the design phase of this project I knew I had to be a low cost producer. That was my driving force because I knew it would give me flexibility......do I sell my excess power or do I heat my water or heat my house? Actually I do all three but its my choice.

            Comment


            • #21
              Originally posted by J.P.M. View Post
              IMO only, most folks would come out ahead by spending most or all initial
              time, effort and resources educating themselves about energy and how it's used.
              My observation as well: most never think about energy at all, just the bills. Explaining it is useless,
              because they aren't interested in thinking about it.

              One thing about my size system, is the rules here give a one for one trade on KWH, no wholesale
              vs retail. However, they never buy anything; its up to me to get it all back. Bruce Roe

              Comment


              • #22
                Originally posted by bcroe View Post

                My observation as well: most never think about energy at all, just the bills. Explaining it is useless,
                because they aren't interested in thinking about it.

                One thing about my size system, is the rules here give a one for one trade on KWH, no wholesale
                vs retail. However, they never buy anything; its up to me to get it all back. Bruce Roe
                Bruce, with a deal like that.....why would you not add to your solar plant and buy an EV? I know you're handy and could DIY.

                Comment


                • #23
                  Originally posted by DanS26 View Post

                  Bruce, with a deal like that.....why would you not add to your solar plant and buy an EV? I know you're handy and could DIY.
                  An EV may work for commuters, but not for this retiree. Some days the Olds doesn't move, but then I might drive
                  across 3 or 4 states nonstop. My record is 1250 miles in 21 hours, no EV can do that. The gas engine does 19
                  mpg, but I put on a 28 gallon diesel tank with a gasoline pickup unit. Bruce

                  Comment


                  • #24
                    Originally posted by DanS26 View Post

                    First off I designed and constructed my grid tied solar system on my own time, thus I do not have any outside labor in the calculation. I sourced as many parts as I could locally getting the contractors discount (since they know and trust me). I over sized the system to twice my annual usage thus getting something like an economy of scale (like pallet pricing). I'm on a "net billing" plan so I could oversize (within reason up to 25 kW AC) without penalty. I added the cost of a couple of inverters in about year 12. I do my own maintenance and I took the 30% tax credit on my sunk costs. There's the numerator.


                    For the denominator I used PVWatts production estimate, which was adjusted to my actual system performance, over a 25 year system life derated at 0.71% per year over that life span.

                    The actual production cost based on the above is $0.0301086 per kWh.

                    Hoosier Energy that produces energy for my local REMC produces at $0.025 per kWh. They sell that production, including distribution and demand charges at $0.065 per kWh to my REMC. My REMC turns around and sells it to me at $0.105 per kWh retail. If I produce excess my REMC will buy it from me at $0.065 wholesale. I think it is a sweet deal.

                    When I was in the design phase of this project I knew I had to be a low cost producer. That was my driving force because I knew it would give me flexibility......do I sell my excess power or do I heat my water or heat my house? Actually I do all three but its my choice.
                    Thank you. Understood (I think). I suspect you did things and got costs most others would or could not do and have access to pricing most other would not. I'd also guess the 25 year life cycle also probably helps reduce the per kWh cost. Did you discount the inverter replacement costs back to present value ? Did you reduce any costs for future salvage value ?

                    Regards,

                    Comment


                    • #25
                      Originally posted by bcroe View Post
                      An EV may work for commuters, but not for this retiree. Some days the Olds doesn't move, but then I might drive
                      across 3 or 4 states nonstop. My record is 1250 miles in 21 hours, no EV can do that.
                      Many could. 18 hours driving at 75mph, 4 charging stops at 45 minutes each, charge rate of 300-400mph, 250 miles per charge.

                      Comment


                      • #26
                        Originally posted by J.P.M. View Post

                        Thank you. Understood (I think). I suspect you did things and got costs most others would or could not do and have access to pricing most other would not. I'd also guess the 25 year life cycle also probably helps reduce the per kWh cost. Did you discount the inverter replacement costs back to present value ? Did you reduce any costs for future salvage value ?

                        Regards,
                        Actually there are credits I did not include.....such as SREC credits and tax benefits from depreciation since some of the system is farm related. And yes I did obtain good pricing on parts not generally available to the general public. But any true DIY'er knows these acquisition tricks with suppliers. In this day and age no one pays retail if you don't want to. It takes patience and willingness to research and asking for multiple quotes.

                        No, I did not discount the inverter replacement costs....the reason being is that I feel that costs will decrease and offset the rate of inflation thus in today's dollars the price will be equivalent. No salvage value......in 25 years I'll be dead and they will just bulldoze the ground mounts and rip the smoking inverters off the wall.

                        But based on my experience to date...I think the the 25 year life is doable. The Kyocera panels are very well made and the Fronius inverters run cool. But you never know.

                        Still, my payback is around 7.5 years and IRR is projected at 12.31%

                        Comment


                        • #27
                          Originally posted by jflorey2 View Post
                          Many could. 18 hours driving at 75mph, 4 charging stops at 45 minutes each,
                          charge rate of 300-400mph, 250 miles per charge.
                          Your numbers were entirely unattainable when I made that trip 4 years ago, starting with an AVERAGE speed
                          5 mph higher than the highest speed limit. Some bad weather brought my average down to 59 mph; I make
                          66 overall when conditions are good. Some day EVs might do what the 77 Olds easily does; I won't be
                          holding my breath. Bruce Roe

                          Comment


                          • #28
                            Originally posted by bcroe View Post
                            Your numbers were entirely unattainable when I made that trip 4 years ago, starting with an AVERAGE speed
                            5 mph higher than the highest speed limit. Some bad weather brought my average down to 59 mph; I make
                            66 overall when conditions are good.
                            Our record was back in 1995; Long Island to Salina, KS (1400 miles) in 20 hours. We had a minivan that got good gas mileage, we were in our 20's and we wanted to see Boulder.

                            I'd love to try that again in our current EV, but I have a feeling that I would now be the weak link in any such attempt to make good time.

                            Comment


                            • #29
                              Originally posted by jflorey2 View Post
                              Many could. 18 hours driving at 75mph, 4 charging stops at 45 minutes each, charge rate of 300-400mph, 250 miles per charge.
                              But why would anyone subject themselves to so many long stops (for charging) that may or may not have a charging station.

                              I am interested in an EV but like bruce if my lifestyle does not include a short commute daily then a short distance vehicle is not practical.

                              Comment


                              • #30
                                Originally posted by DanS26 View Post

                                Actually there are credits I did not include.....such as SREC credits and tax benefits from depreciation since some of the system is farm related. And yes I did obtain good pricing on parts not generally available to the general public. But any true DIY'er knows these acquisition tricks with suppliers. In this day and age no one pays retail if you don't want to. It takes patience and willingness to research and asking for multiple quotes.

                                No, I did not discount the inverter replacement costs....the reason being is that I feel that costs will decrease and offset the rate of inflation thus in today's dollars the price will be equivalent. No salvage value......in 25 years I'll be dead and they will just bulldoze the ground mounts and rip the smoking inverters off the wall.

                                But based on my experience to date...I think the the 25 year life is doable. The Kyocera panels are very well made and the Fronius inverters run cool. But you never know.

                                Still, my payback is around 7.5 years and IRR is projected at 12.31%
                                Understood. Thank you.

                                The reason for my question on inverter replacement cost discounting was, using similar logic to what you describe, if my life cycle time had been longer than 12 years (I expect people will probably be peeing on my grave before that), I figured the cost reductions in inverters would about cover the discounting to present value. Just wondering if my reasoning was shared by someone who seems knowledgeable about life cycle economics.

                                Respectfully different from what seems your opinion however, and keeping in mind as well as acknowledging that every situation is different, with your situation looking a more than a bit off the beaten path of residential PV and so being a bit unusual, IMO only, simply because something will likely last 25 years or more does not automatically make 25 years an appropriate time period to use to gauge cost effectiveness for a residential PV system.

                                Given a long enough time frame, you, I, or most anyone can turn what might be, in a more sober and realistic analysis, a poor decision, into what seems to be a no brainer cost effective scenario, by simply extending the analysis period long enough.

                                Solar peddlers do it all the time.

                                I'd suggest that to the degree most folks - but by no means all folks - don't stay in the same home for 25 years, and also betting that residential PV will add little, if anything, to resale values, using 25 years as a life cycle time to determine cost effectiveness for residential PV may be unrealistic and lead to falsely and overly optimistic economics and poor(er) choices.

                                Sort of off topic, but not unlike a 25 year old derelict looking but still functional solar water heater can do today, there's also the possibility that today's bright, shiny, super duper PV system may be seen as an ugly dinosaur and "old technology" as advances - be they actual or hyped up to sell stuff - make current stuff less desirable in the furture and so lower the property value.

                                Using a longer than appropriate life cycle for an application can be done to imply an artificially rosy economic picture to many, if not most residential applications.

                                So, while I agree that 25 years seems doable in the sense the equipment will last that long, I question whether it's an appropriate length of time to use for more than what may be a minority of situations, and somewhat deceptive to use as a default time frame for Joe & Jane 6-pack who move every 6- 8 years or so, or are retired.

                                Take what you want of the above. Scrap the rest.
                                Last edited by J.P.M.; 01-10-2017, 12:45 PM.

                                Comment

                                Working...
                                X