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Is solar green?

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  • You'd think so, but one shouldn't assume. Back in the early days of solar panels, making solar panels took a LOT of energy.
    nature.com/articles/ncomms13728 has some fresh data on the subject; here's its key graph.
    fig2-payback.png

    According to that paper, polysilicon panels pay back their embedded energy after about 1 year. But the most important figure is 2c, which shows modern panels have lifetime co2 emissions of about 20 grams per kWh... vs. 1000 for coal.

    So, yeah, current solar panels are probably "green". Solar panels from the year 2000, not quite as green.
    17kw. I like science, but I'm no expert.

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    • The sad part is that until someone can find a way to get them solar panels to generate 24/7/365 the power will come from places that are not "green" for a good % of that time unless people become accustomed to being in the dark.

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      • It's not sad - it's a first significant step in reducing the demand and not needing to build any more coal plants in my hood (on top of gaining efficiencies elsewhere like appliances, HVAC and lighting)

        Idle loads during peak summer demand are taken care of and AC cooling is largely powered by the sun in my household. I've also reduced demand for natural gas as I often switch to electric heating on cooler (but sunny) days.

        Those are big steps and with battery revolution taking place, we'll be moving even faster!
        10 x LG300 ACe, 24 x M250 (9.84 kW DC)

        Comment


        • Originally posted by Mike90250 View Post
          Oxford comes pretty close. It's like EV's are "green". They just shift the pollution into somebody elses backyard, and then folks in Santa Monica and San Francisco can feel self righteous because they are green and the peons are not...
          I'm really disappointed (and shocked) with your statement that only non-knowledgeable people (or rich Kochs) make. Are you sure you thought this through? How is pollution shifted exactly? Each gallon of gas that our 24 MPG average gasser burns needs the minimum of 6 kWh to refine (already polluting my place) before it gets to your tank and then exhausted in front of my school while waiting to pick up the kids or zooming on the way to work. My LEAF (2-year olds for $6K now) covers exactly 24 miles on that energy alone and comes with stop/start tech, energy regen, and superior ride for less than a Corolla.

          *Theoretically*, we could swap all cars for EVs overnight, eliminate all pipe exhaust pollution and not need a single extra electron in the process.



          10 x LG300 ACe, 24 x M250 (9.84 kW DC)

          Comment


          • Originally posted by cracovian View Post

            I'm really disappointed (and shocked) with your statement that only non-knowledgeable people (or rich Kochs) make. Are you sure you thought this through? How is pollution shifted exactly? Each gallon of gas that our 24 MPG average gasser burns needs the minimum of 6 kWh to refine (already polluting my place) before it gets to your tank and then exhausted in front of my school while waiting to pick up the kids or zooming on the way to work. My LEAF (2-year olds for $6K now) covers exactly 24 miles on that energy alone and comes with stop/start tech, energy regen, and superior ride for less than a Corolla.

            *Theoretically*, we could swap all cars for EVs overnight, eliminate all pipe exhaust pollution and not need a single extra electron in the process.


            I'm disappointed but not the least shocked by your statement since beliefs of the type you seem to be espousing are, IMO only, usually held by non-knowledgeable people.

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            • Originally posted by cracovian View Post
              *Theoretically*, we could swap all cars for EVs overnight, eliminate all pipe exhaust pollution and not need a single extra electron in the process.
              Yes, in theory. In reality utilities would have to burn more gas and coal to charge all those EV's.
              So in theory you could add a lot more solar and charge during the day. But in reality the grid couldn't handle that additional daytime load.
              So in theory you could upgrade the grid to support that.

              In reality, all of that takes a lot of money, time and nonrenewable resources. So, as always, it's a tradeoff.

              Solar (and EV's) can be _part_ of a reduced pollution economy. But throwing lots of solar at the problem doesn't solve it; it just changes the problem.

              (BTW your LEAF doesn't "come with start-stop tech" - that's only applicable to internal combustion engines that idle.)

              Comment


              • Originally posted by cracovian View Post

                I'm really disappointed (and shocked) with your statement that only non-knowledgeable people (or rich Kochs) make. Are you sure you thought this through? How is pollution shifted exactly? Each gallon of gas that our 24 MPG average gasser burns needs the minimum of 6 kWh to refine (already polluting my place) before it gets to your tank and then exhausted in front of my school while waiting to pick up the kids or zooming on the way to work. My LEAF (2-year olds for $6K now) covers exactly 24 miles on that energy alone and comes with stop/start tech, energy regen, and superior ride for less than a Corolla.

                *Theoretically*, we could swap all cars for EVs overnight, eliminate all pipe exhaust pollution and not need a single extra electron in the process.


                I think you are living in a nice little cozy dream world and really do not understand how electricity is generated, transmitted and consumed world wide.

                EV's will not solve the problem of pollution and will not eliminate fossil fuel from this planet. RE power may reduce fossil fuel usage but even with new battery technology until people greatly reduce their usage (including how they charge their EV's) we will continue to need a lot of power generation from many different fuel sources.

                Comment


                • Originally posted by jflorey2 View Post
                  Yes, in theory. In reality utilities would have to burn more gas and coal to charge all those EV's.
                  So in theory you could add a lot more solar and charge during the day. But in reality the grid couldn't handle that additional daytime load.
                  So in theory you could upgrade the grid to support that.

                  In reality, all of that takes a lot of money, time and nonrenewable resources. So, as always, it's a tradeoff.

                  Solar (and EV's) can be _part_ of a reduced pollution economy. But throwing lots of solar at the problem doesn't solve it; it just changes the problem.

                  (BTW your LEAF doesn't "come with start-stop tech" - that's only applicable to internal combustion engines that idle.)
                  I'm not claiming to be able to solve anything, just addressing the point that I and many others are supposedly just shifting pollution into someone else's backyard to make ourselves feel better or superior... like it's the main motivator and can be summed up with an apples to oranges comparison somehow.

                  I didn't even mention solar in that response to stress that even EVs on the simple dirty grid can make a difference (they're *never* worse than gassers as many claim, period) without the additional hoops that some of us jump through to get even "greener".

                  We've covered 80K electric miles (mostly solar) in almost 6 years in my LaLa land, ran thousands of AC hours on solar, exported thousands of kWhs back to the grid and I didn't shift s#it to anyone in the process. I consumed much less (though paid a lot more but for a good cause )

                  (stop/start, yes, I took an equivalent tech thought shortcut when traction power is running when idling and not heating up the place.)
                  Last edited by cracovian; 03-15-2017, 01:28 PM.
                  10 x LG300 ACe, 24 x M250 (9.84 kW DC)

                  Comment


                  • Originally posted by cracovian View Post
                    I didn't even mention solar in that response to stress that even EVs on the simple dirty grid can make a difference (they're *never* worse than gassers as many claim, period) without the additional hoops that some of us jump through to get even "greener".
                    Depends where you are and what vehicles you are comparing.

                    In Seattle, where most power comes from hydro, an EV is a lot cleaner than a Suburban.
                    In West Virginia, where most power comes from coal, a Prius Prime (operating in gas mode) is a lot cleaner than an EV.

                    I agree that in MOST places you can compare an EV to an average car and it's cleaner overall. But that's not true everywhere.

                    Comment


                    • Originally posted by cracovian View Post
                      It's not sad - it's a first significant step in reducing the demand and not needing to build
                      any more coal plants in my hood (on top of gaining efficiencies elsewhere like appliances, HVAC and lighting)

                      Idle loads during peak summer demand are taken care of and AC cooling is largely powered by the sun in my household.
                      I've also reduced demand for natural gas as I often switch to electric heating on cooler (but sunny) days.
                      Those are big steps and with battery revolution taking place, we'll be moving even faster!
                      100% of the heating and cooling is sun powered at this house, and my electric power too.

                      We have been working on battery technology for a couple centuries, but haven't made
                      enough progress to retire the old standbys. Or propel a car 1K miles a day (routine here).

                      So many people have jumped to the conclusion, that just because our information handling ability is vastly increased (by the
                      development of the integrated circuit), we can somehow change all the rules of the physical sciences. Don't hold your breath.
                      Bruce Roe

                      Comment


                      • Originally posted by cracovian View Post

                        I'm not claiming to be able to solve anything, just addressing the point that I and many others are supposedly just shifting pollution into someone else's backyard to make ourselves feel better or superior... like it's the main motivator and can be summed up with an apples to oranges comparison somehow.

                        I didn't even mention solar in that response to stress that even EVs on the simple dirty grid can make a difference (they're *never* worse than gassers as many claim, period) without the additional hoops that some of us jump through to get even "greener".

                        We've covered 80K electric miles (mostly solar) in almost 6 years in my LaLa land, ran thousands of AC hours on solar, exported thousands of kWhs back to the grid and I didn't shift s#it to anyone in the process. I consumed much less (though paid a lot more but for a good cause )

                        (stop/start, yes, I took an equivalent tech thought shortcut when traction power is running when idling and not heating up the place.)
                        I believe you are trying to both reduce your electric usage and fossil fuel burning which hopefully makes you happy.

                        I too have a home that is totally electric (except for my water heater which is solar thermal heated). I do not have any solar pv panels yet because the cost to install is still high (>$3/watt) with little to no rebates except the FED and an average yearly consumption of 15,000 kWh (down from 25,000 kWh a few years ago) at a cost of $0.11/kWh which makes it hard to get a short time payback even at $3/watt. I plan on building a new home this year around 1600 sq ft which is about 600 sq ft smaller than what I have and will be much better insulated so I expect my electric bill to go down even more.

                        An EV is in my future but I am still waiting on one that has a range closer to > 100 mile/charge with a price tag < $35k. They are coming but not yet, so maybe a hybrid or I wait a little longer.

                        The big issue is with our POCO's here in Florida. It isn't until recently that they (or at least one FP&L) has started to build some very large PV systems 8 @ 75MW each so most generation is either natural gas, coal or nuclear (which the last is just fine with me). So most of my power will not come from RE which means my EV and home electric will probably be from fossil fuel until I can install a pv system myself but again that will only provide me during the 5 to 6 hours during the day.

                        My idea is to keep reducing my electric footprint and use more RE where possible but with 40+ years in the electrical power industry and solar cell technology I understand what it takes to keep the lights on 24/7/365. RE can't do it yet and won't for decades to come without a major shift in culture as to how people use electricity. I hope you understand that I am not against solar or RE as a power source but realistically it won't keep the lights on for me or most people in the world.

                        Comment


                        • Originally posted by SunEagle View Post
                          An EV is in my future but I am still waiting on one that has a range closer to > 100 mile/charge with a price tag < $35k. They are coming but not yet, so maybe a hybrid or I wait a little longer.
                          Bolt comes pretty close ($36K, 240 mile range.) And the Focus is $30K for 115 miles range.
                          Last edited by jflorey2; 03-15-2017, 02:22 PM.

                          Comment


                          • Originally posted by jflorey2 View Post
                            Bolt comes pretty close ($36K, 240 mile range.) And the Focus is $30K for 115 miles range.
                            Yep. I have my eye on both of those. I want to see how they do after a year or so that would be the time I would be looking to retire our Nissan Altima but the wife has her heart set on a small SUV due to our 1100 foot dirt driveway.

                            Comment


                            • Originally posted by cracovian View Post
                              .....*Theoretically*, we could swap all cars for EVs overnight, eliminate all pipe exhaust pollution and not need a single extra electron in the process.
                              And magic fairies dig holes in the earth to obtain the raw materials for the exotic batteries, with no pollution. How many years does a prius or volt battery last? Many times, the car is just scrapped because of the high cost to replace the battery (owners don't have the same subsidy Mfg's have.) My friend is on his 3rd EV, and just trades them in when the battery fades out. Sure the hybrids get good mileage, but they can't haul a load (12,000 lbs) of gravel like my 20 year old pickup & trailer can. But I won't drive my truck in the city, it's not needed, we take the 6 year old subaru instead.
                              Oh, wait, city is 140 miles away, and I have to be home to feed and water the animals tonight. pure EV is not going to make that trip, unless YOU gift me a tesla and a charging station for it. My household 5Kw array is not going to support an EV charger too.
                              Powerfab top of pole PV mount (2) | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
                              || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
                              || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

                              solar: http://tinyurl.com/LMR-Solar
                              gen: http://tinyurl.com/LMR-Lister

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                              • All I know is that since solar power get the energy from the sun, by installing it to our home this helps combat greenhouse gas emissions therefore reduces fossil fuels like natural gas and coal.

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