Hi again John- I just put these values in a project and it hasn't been approved yet.... so I can't speak with 100% certainty: the intent of the distribution losses is to convert the district plant efficiency to an equivalent local plant efficiency. I'm tired and working from memory, but John is referring to the District or Campus ruling for 2009. I believe that you can use actual losses if it is existing and somehow estimate them if you can prove it, which seems impossible. So, you're probably stuck with the defaults. Based on your first comment, I am going to assume that you have district chilled water and district hot water heating. *For cooling:* To populate a net 5% thermal loss for cooling, you can multiply the cooling equipments(s) kw/ton by .95. That will propagate a 5% loss through every plant level energy conversion. The compressor (and sometimes the plant) energy is determined by: (Full load kw/ton)*(tons of cooling demand)*(Part load factor)*(ambient unloading factor). The only number that stays steady in that equation is the kw/ton - so it is the only place to implement a consistent loss of 5%. You may also have to multiply the heat rejection kW/ton by .95 but many times that will be set to "none" for a central plant. *For heating:* It works the same way - but less variables. Just multiply the heating equipment(s) efficiency by .9 and you get a 10% net thermal loss through the whole heating plant. *Where to input it in the Climate Change* I don't know. However, it seems you are substituting climate change for a 4 letter word. That doesn't make any sense. It is totally different - see: It works like this... * if you don't follow the rules, a punishment will come from the sky, and you will go to climate change.... FOREVER and ever. So you better follow the green commandments... **(*citation*: *AlGore 3:16) Cheers, Bob Energy-models.com ?