create a simple bw25 inventory with one emission from biosphere3

bike_inv.py

#!/usr/bin/env python
# coding: utf-8

import bw2data as bd
import bw2io as bi
import bw2calc as bc


bd.projects.set_current("custom")
# restart the database for quick and easy re-use
if 'bike' in bd.databases:
    del bd.databases['bike']
# if biosphere3 database is not in the project yet. This is automatically verified
# it's safe to do this call in any case
bi.bw2setup()
db = bd.Database('bike')
db.register()

# First activity: the bike
data = {
    'code': 'bike',
    'name': 'bike production',
    'location': 'DK',
    'unit': 'bike'
}
bike = db.new_node(**data)
bike.save()

# First input
data = {
    'code': 'ng',
    'name': 'natural gas production',
    'location': 'NO',
    'unit': 'MJ'
}

ng = db.new_node(**data)
ng.save()

# Second input
data = {
    'code': 'cf',
    'name': 'carbon fibre production',
    'location': 'DE',
    'unit': 'kg'
}

cf = db.new_node(**data)
cf.save()

# We add the exchange to the bike activity, from the carbon fiber prod

bike.new_edge(
    amount=2.5, 
    type='technosphere',
    input=cf
).save()


# Verify by printing the exchanges of the bike
a_bike = db.get('bike')
for e in a_bike.exchanges():
    print(e)


# Add another exchange to the carbon fiber production
cf.new_edge(
    amount=237.3,  # plus 58 kWh of electricity, in ecoinvent 3.8 
    uncertainty_type=5, 
    minimum=200, 
    maximum=300, 
    type='technosphere',
    input=ng,
).save()


# Let's find the co2 emission to air from the biosphere tha tis used 
# in the EF V3.0 method:

ef_cc_key = ('EF v3.0', 'climate change', 'global warming potential (GWP100)')
ef_cc_method = bd.Method(ef_cc_key)
ef_cc_method.metadata

# Here are teh actual characterization factors of the method
cfs = ef_cc_method.load()

bio_db = bd.Database('biosphere3')
for a_cf in cfs:
    flow_key = a_cf[0]    
    flow = bio_db.get(flow_key[1])
    if 'Carbon dioxide, fossil' in flow['name'] and ('air',) == flow['categories']:
        print(flow)
        print(flow_key)
        break


# Add the emission to the carbon fiber production


cf.new_edge(
    amount=26.6, 
    uncertainty_type=5, 
    minimum=26,
    maximum=27.2, 
    type='biosphere',
    input=flow,
).save()


# Now we can do a regular LCA, with an actual lcia method

# printing the contribution analysis
import bw2analyzer as bwa


bwa.print_recursive_supply_chain(bike)


lca = bc.LCA({bike:1}, ef_cc_key)

lca.lci()
lca.lcia()
lca.score


bwa.print_recursive_calculation(bike, ef_cc_key)