Adding grams of CO2 equivalents

[GeorgJung]

Hi Hajo,

a widely used quantity these days is carbon dioxide intensity of energy. This is for example expressed as (kilo-) grams of carbon dioxide equivalents per (kilo-/mega-) watt hours (written, e.g., "gCO2eq/kWh").

Unfortunately, there are some problems with the physical precision of this unit:

1. CO₂ equivalents is not the same as CO₂ itself. For example, methane (CH₄) is a potent greenhouse gas (highly absorbent to infrared radiation), with one gram of CH₄ being equivalent to roughly 28g of CO₂.
2. Therefore, the unit is misleading about chemistry: 44g of CO₂ contain 12g of carbon and 32g of oxygen. However I cannot claim that if a process which produces 1 kWh at 44 gCO2eq/kWh it indeed burns 12g of carbon per 1kWh since I am talking about equivalents here. Unfortunately, the IEA does exactly that calculation, ignoring the "eq" in their own unit.
3. The location of the gas is important. If natural gas (basically methane) is in the ground, it does not contribute to the greenhouse effect. If I burn methane I get CH₄ + 2 O₂ → CO₂ + 2 H₂O. So burning 16g of CH₄ (plus 64g O₂), which equate to 448g of CO₂ equivalents, produces 44g of CO₂ and 36g water (vapor!). This means that if I ignore that the methane was not in the atmosphere in first place I can claim that I reduce the greenhouse effect by burning methane at an order of magnitude of one to ten per mass unit! This is clearly nonsense (besides, it ignores the water vapor).
4. Not that it matters here, but on top of all that, methane has a half life of about nine years in the atmosphere, so it breaks down to CO₂ and water on its own...

Therefore I am uncertain about just introducing (prefixed) grams per ((prefixed) watt times hour) as a unit for carbon dioxide intensity. How can I restrict the mass unit to be only valid for carbon dioxide? Is this maybe a non-issue in first place because the mechanisms outlined above have nothing to do with the units? How would I handle this?

Here is a draft of how I described g/kWh as combined unit, simply naming it carbon dioxide intensity. Any criticism would be very welcome!

###  http://www.semanticweb.org/jungg/ontologies/2021/5/ic-units#CarbondioxideIntensity
:CarbondioxideIntensity rdf:type owl:Class ;
                        rdfs:subClassOf <http://www.ontology-of-units-of-measure.org/resource/om-2/Quantity> ,
                                        [ rdf:type owl:Restriction ;
                                          owl:onProperty <http://www.ontology-of-units-of-measure.org/resource/om-2/hasValue> ;
                                          owl:allValuesFrom [ rdf:type owl:Restriction ;
                                                              owl:onProperty <http://www.ontology-of-units-of-measure.org/resource/om-2/hasUnit> ;
                                                              owl:allValuesFrom :CarbondioxideIntensityUnit
                                                            ]
                                        ] ,
                                        [ rdf:type owl:Restriction ;
                                          owl:onProperty <http://www.ontology-of-units-of-measure.org/resource/om-2/hasDimension> ;
                                          owl:hasValue :carbondioxideIntensityDimension
                                        ] ;
                        rdfs:comment "Mass of carbon dioxide equivalents per energy" ;
                        rdfs:label "carbon dioxide intensity" .

###  http://www.semanticweb.org/jungg/ontologies/2021/5/ic-units#CarbondioxideIntensityUnit
:CarbondioxideIntensityUnit rdf:type owl:Class ;
                            owl:equivalentClass [ rdf:type owl:Restriction ;
                                                  owl:onProperty <http://www.ontology-of-units-of-measure.org/resource/om-2/hasDenominator> ;
                                                  owl:qualifiedCardinality "1"^^xsd:nonNegativeInteger ;
                                                  owl:onClass <http://www.ontology-of-units-of-measure.org/resource/om-2/EnergyUnit>
                                                ] ,
                                                [ rdf:type owl:Restriction ;
                                                  owl:onProperty <http://www.ontology-of-units-of-measure.org/resource/om-2/hasNumerator> ;
                                                  owl:qualifiedCardinality "1"^^xsd:nonNegativeInteger ;
                                                  owl:onClass <http://www.ontology-of-units-of-measure.org/resource/om-2/MassUnit>
                                                ] ;
                            rdfs:subClassOf <http://www.ontology-of-units-of-measure.org/resource/om-2/UnitDivision> ;
                            rdfs:label "carbon dioxide intensity unit" .

[ rdf:type owl:Axiom ;
   owl:annotatedSource :CarbondioxideIntensityUnit ;
   owl:annotatedProperty owl:equivalentClass ;
   owl:annotatedTarget [ rdf:type owl:Restriction ;
                         owl:onProperty <http://www.ontology-of-units-of-measure.org/resource/om-2/hasDenominator> ;
                         owl:qualifiedCardinality "1"^^xsd:nonNegativeInteger ;
                         owl:onClass <http://www.ontology-of-units-of-measure.org/resource/om-2/EnergyUnit>
                       ] ;
   rdfs:comment "Amount of energy generated that produced the carbon dioxide equivalents"
 ] .

[ rdf:type owl:Axiom ;
   owl:annotatedSource :CarbondioxideIntensityUnit ;
   owl:annotatedProperty owl:equivalentClass ;
   owl:annotatedTarget [ rdf:type owl:Restriction ;
                         owl:onProperty <http://www.ontology-of-units-of-measure.org/resource/om-2/hasNumerator> ;
                         owl:qualifiedCardinality "1"^^xsd:nonNegativeInteger ;
                         owl:onClass <http://www.ontology-of-units-of-measure.org/resource/om-2/MassUnit>
                       ] ;
   rdfs:comment "Mass of carbon dioxide equivalents"
 ] .

###  http://www.semanticweb.org/jungg/ontologies/2021/5/ic-units#carbondioxideIntensityDimension
:carbondioxideIntensityDimension rdf:type owl:NamedIndividual ;
                                 rdfs:label "carbon dioxide intensity dimension" .

###  http://www.semanticweb.org/jungg/ontologies/2021/5/ic-units#gramCO2perKiloWattHour
:gramCO2perKiloWattHour rdf:type owl:NamedIndividual ,
                                 :CarbondioxideIntensityUnit ;
                        <http://www.ontology-of-units-of-measure.org/resource/om-2/hasDenominator> <http://www.ontology-of-units-of-measure.org/resource/om-2/kilowattHour> ;
                        <http://www.ontology-of-units-of-measure.org/resource/om-2/hasDimension> :carbondioxideIntensityDimension ;
                        <http://www.ontology-of-units-of-measure.org/resource/om-2/hasNumerator> <http://www.ontology-of-units-of-measure.org/resource/om-2/gram> ;
                        rdfs:label "gram CO2 equivalents perkilowatt hour" .

[HajoRijgersberg]

Hi Georg,

Thanx for your issue! This reminds me that we should do something anyway with mass CO2 equivalents and kg CO2 equivalents and so on in OM. And as a second step that we - indeed - could take immediately we could define the carbon dioxide intensity.

How can I restrict the mass unit to be only valid for carbon dioxide?

Good question. I hope to make that a bit clearer in the first bullet below. We do something similar in OM with font size where special length units such as cicero and point are used that are not used for other length classes.

Is this maybe a non-issue in first place because the mechanisms outlined above have nothing to do with the units?

Indeed, I think the four problems that you outline are very important for the domain, but not for defining quantity and unit classes in OM.

Your draft is a very good suggestion! I'm not quite sure yet myself how to design everything exactly, but in any case your input is very valuable! Below I mention some points that come to mind; hopefully those, and your answers to them, will lead to further design:

• First about mass CO2 equivalent: we could define 'g CO2 equivalent' as a mass unit and relate only that one (and kg CO2 equivalent etc.) to a class CarbonDioxideEquivalent, a subclass of Mass. Could there also be related classes (sub- or superclasses I guess) such as GreenhouseGasEmission, CarbonDioxideEmission, etc.? And should we include the word 'Mass' in all of these class names?
• I think we should call :carbondioxideIntensityDimension in your design :massPerEnergyDimension, because dimensions are supposed to be general. I have checked in OM, but no such dimension has already been defined.
• I wouldn't use the axioms I think (or: I haven't used them ever, so don't know exactly if we should or am reluctant to do that because I think it does not adhere to a standard way of working in OM). But am I correct that you use the axioms to narrow the units to CO2? My intention is that that problem would be tackled by the first bullet. And why should the energy unit also be narrowed down? I don't see the term 'CO2' in e.g. "gCO2eq/kWh".

So hopefully all this leads to further decisions, improvements, etc. Looking very much forward to your response!

Best, Hajo

[GeorgJung]

Hi Hajo,

thanks so much!

I restructured according to what I understand from your explanations. It seems a lot smother now. Here are the new declarations:

###  http://www.semanticweb.org/jungg/ontologies/2021/5/ic-units#CarbondioxideEquivalentMass
:CarbondioxideEquivalentMass rdf:type owl:Class ;
                             rdfs:subClassOf <http://www.ontology-of-units-of-measure.org/resource/om-2/Mass> ;
                             rdfs:label "carbondioxide equivalent mass" .

###  http://www.semanticweb.org/jungg/ontologies/2021/5/ic-units#CarbondioxideEquivalentMassUnit
:CarbondioxideEquivalentMassUnit rdf:type owl:Class ;
                                 rdfs:subClassOf <http://www.ontology-of-units-of-measure.org/resource/om-2/MassUnit> ;
                                 rdfs:label "carbondioxide equivalent mass unit" .

###  http://www.semanticweb.org/jungg/ontologies/2021/5/ic-units#carbondioxideEquivalentMass
:carbondioxideEquivalentMass rdf:type owl:NamedIndividual ;
                             <http://www.ontology-of-units-of-measure.org/resource/om-2/commonlyHasUnit> <http://www.ontology-of-units-of-measure.org/resource/om-2/gram> ,
                                                                                                         <http://www.ontology-of-units-of-measure.org/resource/om-2/kilogram> ,
                                                                                                         <http://www.ontology-of-units-of-measure.org/resource/om-2/tonne> ;
                             rdfs:label "carbondioxide equivalent mass" .

###  http://www.semanticweb.org/jungg/ontologies/2021/5/ic-units#gramCarbondioxideEquivalent
:gramCarbondioxideEquivalent rdf:type owl:NamedIndividual ,
                                      :CarbondioxideEquivalentMassUnit ;
                             <http://www.ontology-of-units-of-measure.org/resource/om-2/hasUnit> <http://www.ontology-of-units-of-measure.org/resource/om-2/gram> ;
                             <http://www.ontology-of-units-of-measure.org/resource/om-2/symbol> "gCO2eq" ;
                             rdfs:label "gram carbondioxide equivalent" .

###  http://www.semanticweb.org/jungg/ontologies/2021/5/ic-units#gramCarbondioxideEquivalentPerKilowattHour
:gramCarbondioxideEquivalentPerKilowattHour rdf:type owl:NamedIndividual ,
                                                     <http://www.ontology-of-units-of-measure.org/resource/om-2/UnitDivision> ;
                                            <http://www.ontology-of-units-of-measure.org/resource/om-2/hasDenominator> <http://www.ontology-of-units-of-measure.org/resource/om-2/kilowattHour> ;
                                            <http://www.ontology-of-units-of-measure.org/resource/om-2/hasNumerator> :gramCarbondioxideEquivalent ;
                                            <http://www.ontology-of-units-of-measure.org/resource/om-2/alternativeSymbol> "gCO2eq/KWh" ;
                                            <http://www.ontology-of-units-of-measure.org/resource/om-2/symbol> "gCO2eq/kWh" ;
                                            rdfs:label "gram carbondioxide equivalent per kilowatt hour" .

###  http://www.semanticweb.org/jungg/ontologies/2021/5/ic-units#kilogramCarbondioxideEquivalent
:kilogramCarbondioxideEquivalent rdf:type owl:NamedIndividual ,
                                          :CarbondioxideEquivalentMassUnit ;
                                 <http://www.ontology-of-units-of-measure.org/resource/om-2/hasUnit> <http://www.ontology-of-units-of-measure.org/resource/om-2/kilogram> ;
                                 <http://www.ontology-of-units-of-measure.org/resource/om-2/symbol> "kgCO2eq" ;
                                 rdfs:label "kilogram carbondioxide equivalent" .

###  http://www.semanticweb.org/jungg/ontologies/2021/5/ic-units#kilogramCarbondioxideEquivalentPerMegawattHour
:kilogramCarbondioxideEquivalentPerMegawattHour rdf:type owl:NamedIndividual ,
                                                         <http://www.ontology-of-units-of-measure.org/resource/om-2/UnitDivision> ;
                                                <http://www.ontology-of-units-of-measure.org/resource/om-2/hasDenominator> <http://www.ontology-of-units-of-measure.org/resource/om-2/megawattHour> ;
                                                <http://www.ontology-of-units-of-measure.org/resource/om-2/hasNumerator> :kilogramCarbondioxideEquivalent ;
                                                <http://www.ontology-of-units-of-measure.org/resource/om-2/alternativeSymbol> "KgCO2eq/MWh" ;
                                                <http://www.ontology-of-units-of-measure.org/resource/om-2/symbol> "kgCO2eq/MWh" ;
                                                rdfs:label "kilogram carbondioxide equivalent per megawatt hour" .

###  http://www.semanticweb.org/jungg/ontologies/2021/5/ic-units#massPerEnergyDimension
:massPerEnergyDimension rdf:type owl:NamedIndividual ,
                                 <http://www.ontology-of-units-of-measure.org/resource/om-2/Dimension> ;
                        rdfs:label "mass per energy dimension" .

###  http://www.semanticweb.org/jungg/ontologies/2021/5/ic-units#tonneCarbondioxideEquivalent
:tonneCarbondioxideEquivalent rdf:type owl:NamedIndividual ,
                                       :CarbondioxideEquivalentMassUnit ;
                              <http://www.ontology-of-units-of-measure.org/resource/om-2/hasUnit> <http://www.ontology-of-units-of-measure.org/resource/om-2/tonne> ;
                              <http://www.ontology-of-units-of-measure.org/resource/om-2/symbol> "tCO2eq" ;
                              rdfs:label "tonne carbondioxide equivalent" .

###  http://www.semanticweb.org/jungg/ontologies/2021/5/ic-units#tonneCarbondioxideEquivalentPerGigawattHour
:tonneCarbondioxideEquivalentPerGigawattHour rdf:type owl:NamedIndividual ,
                                                      <http://www.ontology-of-units-of-measure.org/resource/om-2/UnitDivision> ;
                                             <http://www.ontology-of-units-of-measure.org/resource/om-2/hasDenominator> <http://www.ontology-of-units-of-measure.org/resource/om-2/gigawattHour> ;
                                             <http://www.ontology-of-units-of-measure.org/resource/om-2/hasNumerator> :tonneCarbondioxideEquivalent ;
                                             <http://www.ontology-of-units-of-measure.org/resource/om-2/symbol> "tCO2eq/GWh" ;
                                             rdfs:label "tonne carbondioxide equivalent per gigawatt hour" .

I am unsure about :carbondioxideEquivalentMass with :commonlyHasUnit: Should this be the plain units :gram, :kilogram, :tonne or should this be the specific units :gramCarbondioxideEquivalent, etc.?

[HajoRijgersberg]

Hey Georg,

Sorry for my late reply! Thanx for your design! :) It looks good! Few small things:

1. The commonlyHasUnit relation should not be defined for an individual (:carbondioxideEquivalentMass), but for the class (:CarbondioxideEquivalentMass). Like in:

2. http://www.semanticweb.org/jungg/ontologies/2021/5/ic-units#gramCarbondioxideEquivalent

   :gramCarbondioxideEquivalent rdf:type owl:NamedIndividual , :CarbondioxideEquivalentMassUnit ; http://www.ontology-of-units-of-measure.org/resource/om-2/hasUnit http://www.ontology-of-units-of-measure.org/resource/om-2/gram ; http://www.ontology-of-units-of-measure.org/resource/om-2/symbol "gCO2eq" ; rdfs:label "gram carbondioxide equivalent" .

Apart from the hasUnit relation also the hasFactor relation should be added (forgive me my xml syntax):

1 The same thing applies to other units you have defined. (I should add that in the design of OM 2.0 I'm not fully happy with hasUnit and hasFactor as separate properties. Perhaps in OM 3.0 they have to be combined again to a measure. The difficult thing is that it is unsure if such a thing really is a measure. Philosophically difficult. No one really knows.) I have a feeling that the label should be: "gram CO2 equivalent". Similar in other units you have defined. 3. > ### http://www.semanticweb.org/jungg/ontologies/2021/5/ic-units#massPerEnergyDimension > :massPerEnergyDimension rdf:type owl:NamedIndividual , > ; > rdfs:label "mass per energy dimension" . Small thing: the convention in OM is to use a dash and then 'Dimension' (so, '-Dimension') after the quantity name ('massPerEnergy') to distinguish it from the particular quantity. We have not defined that quantity now, but it could have been the case. In fact, not sure if we should define that quantity. And we could add the SI base quantity components as well. In the xml format that I use: mass per energy dimension -2 0 2 0 0 0 0 Looking forward to your response! :) Cheers, Hajo P.S.: The indentation in the xml code disappears, I don't know why. I use spaces, but they are not shown here for some reason. Sorry for the inconvenience.

[GeorgJung]

Hi Hajo,

Thanks!

First, real quick about the indentation of XML snippets. In the markup language here all formatting gets done automatically unless you mark something explicitly for example as code. You do that by using a backtick around a short code snippet, i.e., `code` will become code. Multi-line code examples can be wrapped in triple backticks (```). So

```
   <funny XML syntax> Hallo </funny XML syntax>
         indented line...
```

becomes

   <funny XML syntax> Hallo </funny XML syntax>
         indented line...

(note also the monospace font which is automatically used for such snippets). That might help in the long run...

So, about your comments (Thanks!).

1. I suppose I can delete:

   ###  http://www.semanticweb.org/jungg/ontologies/2021/5/ic-units#carbondioxideEquivalentMass
   :carbondioxideEquivalentMass rdf:type owl:NamedIndividual ;
                            <http://www.ontology-of-units-of-measure.org/resource/om-2/commonlyHasUnit> <http://www.ontology-of-units-of-measure.org/resource/om-2/gram> ,
                                                                                                        <http://www.ontology-of-units-of-measure.org/resource/om-2/kilogram> ,
                                                                                                        <http://www.ontology-of-units-of-measure.org/resource/om-2/tonne> ;
                            rdfs:label "carbondioxide equivalent mass" .

   completely then? Honestly, right now I am not sure why I created it in first place, given that we have:

   ###  http://www.semanticweb.org/jungg/ontologies/2021/5/ic-units#CarbondioxideEquivalentMass
   :CarbondioxideEquivalentMass rdf:type owl:Class ;
                            rdfs:subClassOf <http://www.ontology-of-units-of-measure.org/resource/om-2/Mass> ;
                            rdfs:label "carbondioxide equivalent mass" .

   which is where I should put the commonlyHasUnit property, if I understand you correctly (not quite sure how, but I will let the ontology people here figure that out).

2. Thanks, I added om:hasFactor with float value 1.0 to each of the new units.
3. Introduced the dash. Naming conventions are important. Also, I added the exponents to all seven SI dimensions (basically just copied from your XML snippets above, thanks for figuring all that out!).

So that should handle it. Much obliged this new in-depth review from you! That was very helpful.

Georg

[HajoRijgersberg]

Hey Georg, First of all thanx for the hint about the ```! That will really be helpful in the future, from now on! :)

1. Yes! :) I fully understand you defined that. You are new to the format of OM - you're doing really well!! And it is not even strange that you defined it, since commonlyHasUnit is not implemented as a class restriction (so specifying something about a property that is automatically valid for the instances of the class), but simply as property values only for the class itself (not the instances). commonlyHasUnit is really only a kind of "lightweight" service for the user.
2. Great, thanx! :)
3. And thanx again!

Great that my words helped! And thanx for all your definition work! I'm planning to incorporate your definitions in OM soon! Because a lot of people will be helped by these sustainability definitions. I'll keep you up to date!

Cheers, Hajo

[GeorgJung]

Hey,

[...] since commonlyHasUnit is not implemented as a class restriction (so specifying something about a property that is automatically valid for the instances of the class), but simply as property values only for the class itself (not the instances). [...]

Oh, wow, I think I just learned something about how I really should distinguish between class restrictions and property values as opposed to the obvious, superficial, distinction that I had formed in my mind. This could serve as an academic example. Clear, thanks!

[...] And thanx for all your definition work! I'm planning to incorporate your definitions in OM soon! Because a lot of people will be helped by these sustainability definitions. I'll keep you up to date! [...]

You have no idea how much this is appreciated. We are trying to prove the usefulness of semantic web technologies in a large, diverse, and very relevant technical field. There is skepticism all over. This will help me to meeting that skepticism!

I will go ahead and close this issue as the definitions now have converged to the point there I am happy with them. I noticed that you are reluctant in closing issues whenever there is still discussion possible or some ToDos left for OM...

[HajoRijgersberg]

Hey Georg,

Sorry for my late response! These busy times... And thanx for your response! :)

Oh, wow, I think I just learned something about how I really should distinguish between class restrictions and property values as opposed to the obvious, superficial, distinction that I had formed in my mind. This could serve as an academic example. Clear, thanks!

I can imagine this may indeed a bit surprising. Glad that I could help! :)

You have no idea how much this is appreciated. We are trying to prove the usefulness of semantic web technologies in a large, diverse, and very relevant technical field. There is skepticism all over. This will help me to meeting that skepticism!

Thanx for your kind words! It's great that your showing the benefits of the Semantic Web in this field! It's a pity I have had no time, but I still got incorporating your definitions in OM on my to-do list.

I will go ahead and close this issue as the definitions now have converged to the point there I am happy with them. I noticed that you are reluctant in closing issues whenever there is still discussion possible or some ToDos left for OM...

Great that I could help! Indeed, closing issues is not my strongest point, for the aforementioned reasons. :)

[HajoRijgersberg]

I have reopened this issue, since I plan to incorporate your definitions in OM on short terms.

One thing that I stumbled upon in a related project: I have found very interesting LCA data on pizza (https://doi.org/10.15454/IH2ERI), determined on 80 pizza’s. So, for a range of sustainability properties, mean and standard deviation can be calculated. The authors claim that that goes beyond current LCA tools, where only fixed values (i.e., without standard deviations) are given. The data are very neat. But one thing stroke me: the authors define the property ‘climate change’ with unit 'kg CO2 eq'. What would you say, should I define the quantity :ClimateChange in OM as a subclass to :CarbondioxideEquivalentMass? It seems strange to me to regard climate change as a mass... However, maybe that's very normal in the domain? Or should I rename :ClimateChange into something else? (And if yes, what? Perhaps just leave it :CarbondioxideEquivalentMass?) Looking forward to your reply. Thanx very much in advance! :) I plan to include such in the addition to OM of your CO2 eq definitions.

[GeorgJung]

I have reopened this issue, since I plan to incorporate your definitions in OM on short terms.

One thing that I stumbled upon in a related project: I have found very interesting LCA data on pizza (https://doi.org/10.15454/IH2ERI), determined on 80 pizza’s. So, for a range of sustainability properties, mean and standard deviation can be calculated. The authors claim that that goes beyond current LCA tools, where only fixed values (i.e., without standard deviations) are given. The data are very neat. But one thing stroke me: the authors define the property ‘climate change’ with unit 'kg CO2 eq'. What would you say, should I define the quantity :ClimateChange in OM as a subclass to :CarbondioxideEquivalentMass? It seems strange to me to regard climate change as a mass... However, maybe that's very normal in the domain? Or should I rename :ClimateChange into something else? (And if yes, what? Perhaps just leave it :CarbondioxideEquivalentMass?) Looking forward to your reply. Thanx very much in advance! :) I plan to include such in the addition to OM of your CO2 eq definitions.

Hi Hajo,

long time not looked into it.

No, I would not call "climate change" a property. Climate change is a process (not a quantity!) that involves many factors, most prominently the concentration of greenhouse gases in the atmosphere (in parts per million, ppm). So kg of CO2 eq is not a unit of "climate change"... Clever, but wrong. And not normal. First time I see this.

Mass of CO2 equivalents is a quantity, mass of CO2 equivalents per energy is a quantity, ppm is a quantity, climate change is not.

I am currently on vacation and back in office on August 3, so my replies will be much (much, much) delayed. I'll get back to you soon with more details.

Maybe a quick remark: I recently heard that geologists are using "ocean of water" as a unit, stating that the earth's crust contains "n oceans of water". strange unit, but at least it describes a quantity. Climate change is not a quantity.

Cheers

[HajoRijgersberg]

Hi Georg,

Thanx so much for your view/confirmation! I'll stick to :CarbonDioxideEquivalentMass, and not include :ClimateChange. (ppm by the way is a unit, not a quantity.) Looking forward to more details, but first please enjoy your holidays! :) Fascinating, that unit 'ocean of water'. Of course I would like to include it in OM. For which quantity would it be a unit? Have a good time! :)

Cheers, Hajo

[HajoRijgersberg]

Hey Georg,

I have added the sustainability quantities and units to OM based on your definitions. I forgot to thank you in the upload of the file; I'm sorry for that... :/ Herewith a great thanx to you! I have on my to-do list how to include thanx in OM itself. I'll certainly include you then, hope that approach would be suitable to you. If you could take a look at the definitions, that would be great. You'll find them under the header 'Sustainability Ontology' in the OM file. If desired I can show the definitions integrally in this issue thread; please let me know if that would be more convenient to you.

Cheers, Hajo

[GeorgJung]

:sweat_smile: no worries about the thanks, I am just happy that the CO2 equivalents units are "standard" now.

[...] I have on my to-do list how to include thanx in OM itself.

That will indeed help you in building a community that supports your work on OM in the long run. It also demonstrates other peoples interest in OM, otherwise why would they contribute. So yes, good plan. It is in my interest that the development stays active, I am learning a lot and in the process. That is much more important than seeing my name there. I see precise ontologies as an important tool for further system integration, not limited to renewable energy, so more effort needs to go into this.

I reviewed the 'Sustainability Ontology' part as carefully as I could (keep in mind that I am practically a hobbyist): Looks great to me!

By the way: After reading again and again the class names carbon dioxide equivalent mass (and the like), I keep brooding about an insufficiency of the English language. What we really mean is the mass of carbon dioxide that in its effect on the atmosphere is equivalent to the given mass of whatever else we are actually looking at (e.g., methane). Wouldn't that be the equivalent mass of carbon dioxide? I can replace 1g of methane with 28g of CO2. So 28g is the mass of CO2 equivalent to 1g of methane. To be clear, we have to keep the names as they are, because this is what is generally used, but somehow I cannot think about it too much without getting insecure about what we say not being what we mean... :thinking: To me it is like $\frac1{28}$ should be the (specific) carbon dioxide equivalent masse of methane... Ignore this! 😅

[HajoRijgersberg]

😅 no worries about the thanks, I am just happy that the CO2 equivalents units are "standard" now.

Thanx! :)

That will indeed help you in building a community that supports your work on OM in the long run. It also demonstrates other peoples interest in OM, otherwise why would they contribute. So yes, good plan. It is in my interest that the development stays active, I am learning a lot and in the process. That is much more important than seeing my name there. I see precise ontologies as an important tool for further system integration, not limited to renewable energy, so more effort needs to go into this.

Thanx for your words and I fully agree! Hope I can tackle this soon and trace back all people who contributed to OM in some way. But I will! :)

I reviewed the 'Sustainability Ontology' part as carefully as I could (keep in mind that I am practically a hobbyist): Looks great to me!

Thanx again. I think it is especially important that you look at precise names etc., based on your experience in the field. As you have done with reflecting on carbon dioxide equivalent mass:

After reading again and again the class names carbon dioxide equivalent mass (and the like), I keep brooding about an insufficiency of the English language. What we really mean is the mass of carbon dioxide that in its effect on the atmosphere is equivalent to the given mass of whatever else we are actually looking at (e.g., methane). Wouldn't that be the equivalent mass of carbon dioxide? I can replace 1g of methane with 28g of CO2. So 28g is the mass of CO2 equivalent to 1g of methane. To be clear, we have to keep the names as they are, because this is what is generally used, but somehow I cannot think about it too much without getting insecure about what we say not being what we mean...

I feel what you mean. Indeed in English something like the equivalent mass of carbon dioxide would be phrased as carbon dioxide equivalent mass. Perhaps we should think of dashes between - at least - the words 'carbon' and 'dioxide', but perhaps also between 'dioxide' and 'equivalent'. And indeed, I fully agree with you that however non-ideal the name may be, we should keep it that way because the term is generally referred to this way.

To me it is like 1/28 should be the (specific) carbon dioxide equivalent masse of methane...

I feel what you mean! :D

Ignore this! 😅

No, I like such reflections/considerations! :D