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DeltaE / Canada-U.S.-ElecTrade

The Role of U.S.-Canada Electricity Trade in North American Decarbonization Pathways
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Canadain Input Activty Ratio Values #13

Closed trevorb1 closed 3 years ago

trevorb1 commented 3 years ago

I am fairly confused about our Input Activity Ratios.... So I am not sure if this is an actual issue or just something I need help understanding! :)

Currently for all technologies (excluding FC and P2G) we use the same input activity ratio as the US model. The source for the IARs are from Table 8.2 (pg 105) in the 2017 AEO report (first picture). The Heat Rate (Btu/kWh) should be used as the input activity ratio.

I have two main questions:

  1. Why are we inputting numbers divided by 1000 from that shown in the table? For example. the bio heat rate gives a value of 13500 Btu/kWh, but we input a number of 13.5 into our model? From this EIA link it seems like we should be inputting in units of (Btu/kWh) which is shown in the table as 13500?

  2. In some cases the input activity ratio matches up with the table. For example, Bio IAR starts and ends at 13.5 in our data file which matches the Bio Heat Rate in table 8.2. In other cases, our IAR changes throughout the model years and does not match up with table 8.2. For example, our gas IAR starts at 9.69 and decreases to 9.08 in 2030 before staying at this value for the remainder of the model. Since table 8.2 values are for 2016, and our first year is 2019, I looked at the US data because their model starts in earlier then ours. Their gas data (for both NGCT, NGCC) starts at 9.92 in 2015 and then steadily decreases to 9.08 in 2030 (second picture). My questions are, I am unsure where the reduction factor is coming from, why the reduction is starting at 2015 instead of 2016, and why the reduction is ending in 2030

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trevorb1 commented 3 years ago

Looking at Gopika's units, she is inputting the activity ratio in units of MMBtu/MWh. So dividing the heat rate value by 1000 is justified. I am still confused though on why she is inputting her activity ratio in MMBtu/MWh opposed to Btu/kWh?

The only thought was for numerical scaling when the model is being solved. But Im not sold on that because the calculated variable cost with running the technology would be very different if the efficiency was a 1000th of what is supposed to be?

trevorb1 commented 3 years ago

After re-reading the EIA Link above, it seems like we should be dividing the equivalent Btu content of a kWh of electricity (3,412 Btu) by the heat rates in the table. This Wikipedia page also says a similar thing.

For example, Coal with 30% CCS has a heat rate of 9750 Btu/kWh -> efficiency of (3412Btu/kWh) / (9750Btu/kWh) = 35%. Then our input activity ratio will be 1 / efficiency = 1 / 0.35 = 2.858 as per page 14 in this osemosys user manual

In any case, I still disagree with just diving the heat rate values by 1000 and inputting those into the model. @Sfusina let me know what you think. I can update our IAR numbers and type this up in the Wiki if you are happy with this justification.