Cogeneration for Dummies

[sld]

Thanks, Antti! yes, my data is...how to say it, "shaky"...what is available...

[sld]

This is not a TIMES question really, but a more general modelling one. As you can see from my previous posts, the data I have for cogeneration, ranges from "not very good to none”. In some cases, I don't have thermal capacity, thermal efficiency; absolutely no costing data includes steam production, etc.

So I am trying to decide what the best way to model it is. In the region I am modelling cogeneration represents 15% of total installed electricity capacity. And from that 15%, 20% goes to the grid, 80% is consumed in-house.

I am thinking of modelling CHP plants as power plants, because it is the only way to get results more or less reliable. And to create an industrial demand for the fuel that was going to be used if modelled as CHP (because when I tried modelling as CHP plants, the processes always consumed a lot less fuel than I was expecting them…based on my wonderful dataJ). And also I have to model  the  losses that were to happen in secondary generation/steam production.

I know it's the not the correct way, and I know steam is not going to have a value, but I know my cogeneration data is awful.

I could also take some cogeneration plants around the world and say, due to lack of data I assume they behave in the same way. And that more data needs to be made publicly available …

Any thoughts, anyone has any new ideas/thoughts about this scenario?

Thank you very much for reading and commenting

[Antti-L]

I hope others can give you some good ideas, but here are my thoughts about it:

If you don't have any value for steam/heat in your model, I don't think it makes any difference whether you model the CHP plants as pure power plants or CHP.  In both cases, you need the efficiency, availability, and cost data.  If you have the data for these parameters, you can model the technology equally well as a pure power plant, or a CHP plant with NCAP_CHPR(FX)=0. The results would be identical. And as your steam has no value, you could even add some realistic NCAP_CHPR(FX)=X, and you would still get identical results in terms of fuel consumption and electricity generation.

But because you say that cogeneration represents 15% of total installed electricity capacity, it seems cogeneration already has an important role in your system.  If you are going to model options for new investments into power plants, it would thus seem resonable to include CHP as an option also for the future. But to do that, you would need to model the demand for the process steam / heat, which the CHP plants can deliver, so that you would also have a value for the steam/heat.  Otherwise you will not be able to model the competitiveness of CHP in your system in a realistic way.