forums.itreetools.org

i-Tree Support Forums
It is currently Tue Oct 17, 2017 10:42 pm

All times are UTC - 5 hours




Post new topic Reply to topic  [ 2 posts ] 
Author Message
PostPosted: Tue Sep 05, 2017 1:12 am 
Offline

Joined: Wed Mar 08, 2017 1:19 pm
Posts: 2
Hi,

I'm struggling to understand the various energy benefits included in iTree reports. Specifically, I need to know why there are both kWh and BTU values for heating benefits instead of a single quantity of energy. These values appear to be independent, as they are summed to the total energy benefit. The "i-Tree Streets Reference City Community Tree Guides" also lists both outputs for heating, with no explanation of the difference. None of the iTree documentation seems to provide details on why there are two values.

A brief overview of "Carbon Dioxide Reduction Through Urban Forestry" indicated that all heating methods were converted to natural gas and measured in BTU. Given that, I fail to understand what the kWh value in iTree actually represents. The report also indicated that cooling was achievable only through electricity, and so was measured in kWh.

When I look at a project like the NYC street tree map, only kWh is listed as a benefit. Did they convert the BTU to kWh, or exclude it?

Any guidance would be appreciated.

Thanks!


Top
 Profile  
 
PostPosted: Mon Sep 11, 2017 9:00 am 
Offline
i-Tree Team

Joined: Fri Dec 21, 2012 7:45 am
Posts: 113
Hi,
The kwh and btu are both included to represent the local mix of home heating choices. You are correct that the model does calculate a single btu necessary to heat any average home but that "combined conversion factor" is then parsed out to kwh and btus based on the average local mix of electric and gas heat. This parsing out is necessary because of the differences in the cost of gas versus electricity as well as differences in the amount of carbon produced by each.

The methods are indeed included in the "Carbon Dioxide Reduction Through Urban Forestry Paper" (https://www.fs.fed.us/psw/topics/urban_forestry/products/cufr_43.pdf. However, that paper is only interested in estimating total carbon rather than trying to put a dollar value on it. Tools like i-Tree Streets parse out those different heating methods expressly so that they can be properly valued given differences in prices between electricity and heating fuels.

As far as the NYC Street Map I am not sure how they applied the model. That was not a US Forest Service project. I would recommend contacting them directly to see how they generated their estimates.

Thanks for your questions.
Jason


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 2 posts ] 

All times are UTC - 5 hours


Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
cron
Powered by phpBB® Forum Software © phpBB Group