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  • +1

    Straight up question:

    Setting aside the financial costs and benefits of solar panels, does it make any difference to the total carbon released into the environment if we install solar panels, and all the power we currently use is electric?

    I believe (and please correct me if I am wrong) that electricity is already covered by the Emissions Trading Scheme (ETS).

    If so, then any electricity that we produce from a solar panel at home, is electricity that we don't purchase from a generator / retailer, and are carbon credits that we don't (effectively) use up.

    That would mean that the carbon credits we did not use, are now available for someone else to use.

    If there is a binding cap on emissions under the ETS, that seems to imply that installing solar panels will have zero impact on the total carbon emitted into the environment?

    Am I missing something obvious, or is that how it works, and is supposed to work?

    • +1

      All grid produced electricity produces carbon. Renewables have a small carbon footprint, peaker production via gas and coal obviously have a huge impact.

      PV solar has a one-off carbon footprint for the carbon required to produce the panels, this is often ignored in these "green" discussions (also eg how you need to use the same "reusable" shopping bag for X number of years just to be equivalent to the carbon footprint of using plastic bags, but no one mentions this).

      Once you're set up though, your reduction in demand from the grid directly reduces demand from suppliers, meaning their carbon emissions goes down.

      This site reckons NZ's carbon emissions is 98g of carbon per kWh of electricity (data from 2016): https://thedig.nz/transitional-ecology/summary-the-clean-energy-policy/#:~:text=In%202016%20(the%20latest%20year,predicted%20to%20get%20even%20better.

      Thus for every kWh of electricity you no longer need from the grid you're saving 98g of effective carbon. In reality it won't be like this, since you'll probably need some grid electricity during peak demands on cloudy days, and peak power is the most emissions heavy (due to peaker producers as above). The other difficulty is that some of the carbon footprint of the producers is associated with manufacturing of their equipment, which is still there, so you only reduce "operational" emissions not total emissions.

      The biggest question is, based on how much electricity you can tangibly make from your PV over the life of the PV, does the carbon footprint of producing the PV, inverter, etc offset the carbon emissions from the grid electricity you now no longer need? And I don't know the answer to that.

      • Okay - so it sounds like the total ongoing (ignoring production costs of the panels) carbon emissions will the same with or without the panels?

        If we include the production costs (even if they are very small) then the total carbon emissions would be higher?

        • No, with PV you're buying less electricity from the grid, so that 98g per kWh (or whatever it is currently) is a saved (reduced) emission. As your PV has no ongoing carbon footprint.

          • @SrsSarcasM: Okay, but with a binding cap on emissions in NZ, the carbon credit that I did not purchase will now be purchased by someone else, so the total emissions will be exactly the same (ignoring the production emissions of the panel)?

    • If you trace the carbon cost of manufacturing solar panels, installation, life-span, payment subsidies for unusable power on the local grid, massive taxpayer subsidies, it all equals political science.

  • +1

    One of the biggest deceptions that big oil has managed to do is their PR campaign that successfully shifted the blame from the big corporate emitters to your own personal responsibility.

    100 companies cause 71% of all global emissions in the world.

    They tell you you're the problem and then they make money selling you the solution.

  • The idea of a personal carbon footprint was popularized by a large advertising campaign of the fossil fuel company BP in 2005. It instructed people to calculate their personal footprints and provided ways for people to "go on a low-carbon diet". This strategy, borrowed heavily from previous campaigns by the tobacco industry and plastics industry to shift the blame for negative consequences of those industries onto individual choices.

    BP made no attempt to reduce its own carbon footprint, instead expanding its oil drilling into the 2020s.


  • +1

    @Bill & @Senior Mouse:

    I'm not entirely sure what you are saying?

    Do you mean that individuals should not care about their own 'carbon footprint', and should continue to support products (such as petrol) from fossil fuel companies (such as BP), rather than moving to lower 'carbon footprint' options (such as EVs)?

    • No, what I am saying is your carbon footprint doesn't matter when corporations are allowed to do whatever they want. A personal carbon footprint overshadows the corporations that are the true emitters. When it is profitable to release carbon, it will never cease.

      It is like a tobacco company telling people to not smoke for their health while producing more cigarettes at a larger scale to try and lower prices all while lobbying the government against anti-smoking legislation and impeding the development of a healthier alternative to try and keep people using cigarettes for longer.

      Regulation is what will create change, personal changes do nothing.

      • Probably true - if I stop buying carbon emitting products, the corporations will just keep on producing them, so no point in being less wasteful.

        • Yeah, only when there is a large actual impact that production changes, eg, the pandemic reduced the consumption of gasoline.

          One of the best ways to reduce your carbon footprint is to move your kiwisaver/funds into those climate friendly funds. Way more effective than anything else.

          • @Bill: I don't think that would make any difference - if I sell a share in, say, BP, someone else buys it - zero sum game. BP itself does not care, nor does it make any difference to the business per se.

            • @Alan6984: No, I read that shifting funds make a massively greater impact than going carbon zero, solar panels, ev. Don't really know why either. BP definitely cares about the demand for their shares and thus the price.

              • @Bill: I would have doubts about the source.

                I have no idea what their share price is, and it doesn't really matter, but lets assume the bid-offer spread is $1.00 to $1.20 both equalling the volume I want to sell, the last trade was at $1.10, the market depth goes up / down $0.01 at a reasonable volume (more than I would be trading).

                If I accept the bid, then I move the bid-offer spread 'down' to $0.99 to $1.20, and the last trade would now be $1.00 (if anything, would have to be regarded as a price drop, certainly not an increase), but if I make a new offer of $1.19, and it is accepted (in full with no additional trades), then I leave the bid-offer spread at $1.00 to $1.20 but with a new last trade at $1.19 (if anything, would have to be regarded as a price increase increase, certainly not a decrease).

                So selling my shares, depending on whether I wanted to sell at 'any price I can get as quickly as possible' or 'the best price I can get as quickly as possible' might increase or decrease the recorded share price.

                Either way, BP is in exactly the same position is was before, whether my trade (with someone who wanted to buy) increased or decreased the last traded price and / or the spread.

    • Yes, Alan.

      Should we care about our own "carbon footprint," or is it just obfuscation? Is it marketing from big cooperation to vilify the users? Yes and yes.

      Large cooperations that are proven not to care about lives of humans, animals or the ecology would like us to think so.

      Same is true in war; if there is an enemy, the people forget about the atrocities committed by those whom feed them.

      We can find interesting underlying propositions by apply philosophical skepticism. What would be the point of being "green" if it just means we consume more?

      The irony of (reducing) consumption on a deals website is not lost on me.

      • Hi Senior Mouse,

        Sorry - I'm not following you.

        You are saying that we should reduce our personal 'carbon footprint'? That seems to be the opposite of what you say above?

        I guess I misunderstood one or other of your posts?



        • Sorry if my reply is confusing.

          I'm saying probably won't matter either way, but it's the thought that counts!

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