jupiter1124

Thanks for explaining, I understand what you mean now. I think there is quite a big difference between the two, though. Batteries don't themselves generate energy, so their production will always be energy negative, regardless of whether it's green energy to produce them or not. Whereas the production of fuels is always energy positive (i.e. you get out more energy than you put in). If it isn't, then it's not an economic investment! If I have 100 kJ of dirty energy and I use it to produce 1000 kJ of biofuel, that's a tenfold multiplication in the amount of energy I have, without increasing my carbon output. If I use it to produce 1000 kJ of dirty energy, that's a tenfold multiplication in the amount of energy I have, AND a tenfold increase in the carbon output. So yes I do in fact think that it is "worth it" to use dirty energy to produce clean energy from the carbon perspective, assuming of course there is more clean energy out than dirty energy in (which, unless you don't like money, will always be the case). That's why this wouldn't ever happen: One would never burn 1000 kJ of dinodiesel to produce 500 kJ of biodiesel. One might burn 500 kJ of dinodiesel to produce 1000 kJ of biodiesel, but that is still a net positive because it's 500 kJ of net clean energy! Better still of course would be use clean energy to produce fuel, as well as batteries, power the grid, and fill those batteries. We're a way off away from that but moving in that direction, and batteries are DEFINITELY part of that solution, even if we do need to bootstrap their production with some carbon emissions.

It doesn't require net energy to make it. The production of biofuels such as HVO is still energy positive. If carbon neutral energy is used to make it, then it is indeed carbon neutral. Let's say a factory produces 1000 kJ of biofuel, and it uses 100 kJ of dirty energy to make it. The factory produced 900 kJ of net energy, 90% carbon neutral. If the factory uses 100 kJ of that biofuel's energy to make the next batch of 1000 kJ of biofuel, it has now made carbon-neutral biofuel. (If you want to be extremely technical, you can say it's now 99% carbon neutral, and the next batch will be 99.9%... so you can mathematically say it tends towards carbon neutrality. But, I think, this is pedantry rather than a helpful classification of the fuel by carbon impact). I'm feeling confused by how you think my use of the term carbon neutral would be used to describe batteries. Would you be willing to explain what you mean so that my need to understand can be met? I can understand this point of view, and there's definitely a practical aspect to this as we make the necessary changes - for now, most lorries use dirty diesel, and so transporting biodiesel by lorry means the practical usage of biodiesel isn't really carbon neutral. However, it is more helpful and more accurate to point out that while the biodiesel itself is in fact carbon neutral, it's the transportation that is the problem in this case. All the carbon sequestered in it was captured from the atmosphere, not extracted from the ground - and releasing it back to the atmosphere should not be considered a failure or a tragedy. The releasing of carbon captured recently should be considered a neutral activity. There are lots of reasons why biodiesel isn't the complete answer (land use change, expense, local pollution) but carbon emissions aren't one of them. The carbon emitted during production and transportation applies to dinodiesel too.

I guess you can call it this. I would call it fossil fuel companies promoting a misleading use of the term. Perhaps you'll find it more agreeable if I talk about carbon that's part of the carbon cycle, and carbon that's not (mineral carbon). I'm trying to shift a perspective that is common and unhelpful. No, because a forest is part of the carbon cycle and always will be, the mine is not and never will be. We should stop entertaining the idea of "offsetting" ancient carbon with carbon that's part of the carbon cycle, because it's just not realistic. The quantities are just too great and the land required is just too huge. Plus it involves trusting that the forest will remain in perpetuity. Cutting a forest down is not a neutral activity, but I would call that land use change. Burning the wood (or letting it decompose) is part of the carbon cycle. If you replant the wood continuously to replace the chopped down wood, there is no land use change, and this is a carbon neutral activity. As it shouldn't be, because we're just releasing the same carbon that we removed from the atmosphere by growing our biofuel (food). It's carbon cycle carbon. Of course if you count the agricultural machinery, the transport, etc, then no it wasn't carbon neutral, but it's unhelpful to call food carbon emitting when it's not the food's "fault", but the fossil fuel's "fault". You're pointing the finger at the wrong things. Food itself can't be anything other than carbon neutral because humans are fueled by the very same energy chemical carbon bonds that were created by the sun converting carbon dioxide into food. It does, but in theory, if you were to fuel the ships with those wood chips, then it would be carbon neutral. In the context of an extremely integrated carbon based energy economy, I guess not, but the point of the term (for me at least) is to separate out those things that would be carbon neutral if not supported by a whole bunch of peripheral carbon releasing activities. Otherwise the term isn't helpful. If I grow a broccoli in my garden, eat it, then breathe out carbon dioxide, this is a carbon neutral activity. You could of course argue that because I drove to the shop in my ICE car to get the seeds, that it isn't, and while you're technically correct, it's not helpful because it's the DRIVING THE ICE CAR that's the issue, not the growing of the broccoli. Fossil fuel companies know that conflating the two helps their case, if you can't even grow a broccoli without carbon, then what's the point in even trying to reduce carbon emissions. Heck we even breathe out carbon (!) I couldn't agree more, but that's beyond the scope of what we can do personally.

Yes, me. HVO is carbon neutral. Anyway you can see why I avoided mentioning HVO at the start of this thread as i knew where the conversation would go 😅

That's not really a useful thing to say. The fuel itself is carbon neutral. It's a wholly unreasonable standard to state that the entirety of the energy grid and transportation needs to be carbon neutral before any of the products it touch can be carbon neutral. I consider all biofuels to be effectively carbon neutral, because they are part of a closed loop carbon cycle. Grow plants - absorb carbon - burn plants - release carbon. The truth is a little more complicated than that, but that's the basic principle. Possibly there was biomass growing before the biofuel plants, and possibly that was slightly higher in carbon content (e.g. rainforests). Possibly the biofuel was created with energy derived from fossil sources. Possibly it was transported with fossil fuels. But all of those things serve to muddy the waters. The problem with your objection is that it equates HVO and mineral diesel as "both not carbon neutral", but the difference is that while both diesel and biofuel takes energy to produce and transport, burning the diesel itself is the primary source of carbon in the one, and burning the HVO does not itself contribute carbon. This is exactly the type of obfuscation that is employed by the oil companies and others with a vested interest in fossil fuels, which is why I must protest. THIS IS DONE DELIBERATELY in order to try to distract people from the basics, which is that growing and consuming biomass is ultimately carbon neutral. There's only one major contributor to carbon, and that's the mining of fossil fuels and other carbon-containing minerals (for example limestone for cement). If we ceased the mining of carbon containing minerals, carbon neutrality would naturally follow, because all other carbon is part of the carbon cycle. It's really as simple as that, so whenever I find someone talking about farming or burning wood or anything else being "bad for the environment", I try to point out that these issues are trivial in comparison to the biggest problem - that humans are increasing atmospheric carbon concentration to prehistoric levels through the release of prehistoric carbon.

Yes, it is.

Something has to suffer for carbon neutrality, whether it be the birds and wind turbines, deforestation for biofuels, or meltdown risk and nuclear. Conflating all the various "green" issues together is doing us a disservice, and it's not really that useful to compare carbon neutrality with habitats. Sad that local wildlife is suffering but that's unfortunately that's what happens when you share a planet with humans.

HVO should probably be completely exempt from all additional duty besides regular VAT. It makes no sense that a "sin tax" would be applied to discourage people from using it, since it's basically carbon neutral and much cleaner than regular diesel besides. Having said that, my understanding is that there isn't anywhere near enough HVO to meet demand even with the tax, so this would just push the prices up to similar levels. Therefore I guess no harm done, really.

In my view it was rather presumptuous and in fact unfair of them to make such a suggestion. Prior to getting my mooring, as a liveaboard continuous moorer I declared 10% propulsion, and kept detailed logs that showed that this was in fact a fair split for my usage to within around 5%. I was never investigated. Now I declare 60/40, which is close to my actual usage.

VERY interesting, does this imply that boat electrical generation by diesel should be done with "propulsion duty paid" red? Since I only have the one engine and it serves triple duty (heating / electricity generation / propulsion) it's not that easy to tease apart which is what. The compromise I have come to is to just treat hours cruising as "propulsion" and hours running stationary as "domestic". This in itself is erring on the side of the tax man since I'll cruise to charge my batteries as well as to move. But to be honest the stationary running of the engine is mostly about electricity, the heating is really just a bonus (not enough to not run the solid fuel stove). So does that mean I should be paying 100% "propulsion" now? No, I realise that there are two rates for tax, one for propulsion and one for domestic. The split is about how much of each you are buying, and therefore how much tax you pay. What I perhaps wasn't aware of is that tax is a fixed price per litre, rather than a % of the sale price? I assumed that it worked like VAT (e.g. 40% of the sale price). Thanks, this was my question. I expect so too, but would be interesting to see them justify it, because it would really make it directly about the colour of the diesel in your tank rather than the tax paid. A corollary interesting court case would be someone who polished / distilled red diesel somehow to remove the dye. If it's really about the colour, then that should be ok right?

Yeah white diesel is generally cheaper at the pump, but was just curious if it's the same in terms of tax. As in, if I was to fill a diesel car with red diesel from a marina 100% propulsion split, would it theoretically be properly taxed (i know his majesty's customs officers would just see the red dye and lock me up and throw away the key in practice)

The message I sent was to ask these questions (seller didn't think to put this information in the ad). Ok - so this indirectly answers my question, in that HVO is subject to the same red/white duty rebate. That doesn't really seem reasonable considering that surely part of the reason for fuel taxes should be to encourage cleaner greener choices. But I'm more interested in the practicality than the philosophy... Out of interest is "white diesel" / DERV equivalent in terms of tax to "red for propulsion" (i.e. the e.g. 60% propulsion split)? And then red diesel (i.e. the e.g. 40% domestic split) the same tax as what is paid for agricultural diesel? Why? Surely it's my choice if I wish to run a diesel generator? I have plenty of cause to (rural location, off grid equipment needing power)

I was expecting "a few hundred" for the tank, by which I mean 300-500 or so. I had pictured a basic steel box, was aware that was probably naive though. But you're right in the scheme of boating things even a grand isn't that bad. I have sent this seller a message as this is more in the region of what I was expecting. https://www.ebay.co.uk/itm/355531739957 Still, I dont really have a solution for the propulsion duty other than buying red diesel separately from a marina in quantities equal to my estimated propulsion usage. Come to think of it, do you have any idea how duty works for HVO? It would seem unfair to charge a propulsion surcharge on HVO, so perhaps I can reasonably use 100% "domestic" HVO even for propulsion?

Hmm, ok I was under the impression that this was a reasonably common thing to do. Surely there are some households that use diesel for home heating, or generator use for off-grid electric? Cost isn't actually the only reason. I also had another reason for doing this, being that I was interested in buying HVO to reduce my environmental impact, but I didn't want to complicate the original question. I don't know anywhere I can get HVO for use as boat fuel other than if I get it delivered, at least not in Notts. Anyways maybe since my garden is on water that this won't be an option for me anyway. I really don't want to do too much hoop jumping. Signing a declaration is one thing but having to inform the environment agency and what not is unappealing. Also, if I can't pay the propulsion myself directly then it's a bit of a non starter as I'd have to fill 60% of my tank at 100% "split" of expensive marina diesel anyway. But the main problem is needing 500l at a time and only having a 230l tank (and maybe 60l of jerry cans) I can't really meet the 500l minimum delivery without getting a storage tank. The bowser sounds like a pretty good idea, and I have a spot I can hide it in my garden. But a grand ... it will take a few years to pay back the cost of that, apart from the other issues above. I think you've convinced me that it's trips to the marina. I'd much rather go the other way sometimes 😂

I'm considering buying a 500l diesel tank to put under my deck and getting a load of red agricultural delivered, instead of having to take a trip to the marina to top up my 230l boat tank all the time which is a couple of days cruise from my EOG mooring. My road access is a few feet higher than my boat and so I think I'd be able to get away with gravity feeding the fuel to the boat. I know a couple of forum members get diesel delievered this way and its alot cheaper. I just had a few of questions about this... 1. Whats required in terms of a tank? What regulations should I be following to store the diesel in my garden? What's the cost of a tank like this and any recommendations of manufacturers / products / etc? I assume I'll need a filling hose as well. 2. I expect that their main customers are agricultural and construction. What is the attitude of bulk fuel sellers to selling to narrowboaters? Am I going to get a lot of questions about my identity, justifying the small quantity and that I'm not going to use it in a road vehicle etc.? 3. How does duty work if I buy diesel in this way? I assume that the fuel supplier would not deal with the boater split. Can I pay the propulsion tax directly and if so, how? 4. Should I worry about storing this kind of quantity for long periods? I should think that 500L will last me a whole year, so I am a bit concerned about bug and water ingress. Any other thoughts would be really useful too. TIA