Getting started

Installation

Install utilityLCA from PyPi:

pip install utilityLCA

Example

To get started with utilityLCA, you need to create a steam distribution class. Passing a name is mandatory, while the other parameters have default values. The following code shows how to create a steam distribution model with custom parameters.

from utilitylca import steam_distribution_conventional as sdc
from simodin import interface as link

my_model= sdc.steam_net('steam net', needed_temperature= 180, wind_velocity=3, heat=1E6 ,
                    heat_capacity_pipe_network = 20E6,
                    insulation_thickness=0.1
                    )

The full list of parameters and their default values are:

Parameter	Unit	Default value
Makeup factor	%	5
Ambient temperature	°C	20
Leakage factor	%	7.5
Steam generation pressure	bara	130
Pipeline capacity	MW	20
Process heat demand	MW	1
Wind velocity	m/s	3
Insulation thickness	m	0.1
Environment		Air
Pipe length	m	1000

The parameters can also be changed later explicitly by:

my_model.params['needed_temperature']= 200

Or be passed to the init_model or calculate_model method. In init_model method, the model is initialized and the parameters are used to set up the model structure. In calculate_model method, the model is calculated and the parameters are used in the calculation.

my_model.init_model(wind_velocity=2)
my_model.calculate_model()

To link LCA datasets to the model, the technosphere flows needs to be generated and the SiModIn interface class created:

my_model.define_flows()
my_interface= link.modelInterface('steam_net', my_model)

For LCA calculation, the needed brightway25 dataset needs to be assigned to the technosphere flows.

The brightway25 code for searching ecoinvent datasets are shown here:

import bw2data as bd


bd.projects.set_current('steam_distribution')

ei=bd.Database('ecoinvent-3.11-cutoff')

ei_heat=[act for act in ei if 'heat production, at hard coal industrial furnace 1-10MW' in act['name']
and 'Europe without Switzerland' in act['location'] ][0]

ei_water=[act for act in ei if 'market for tap water' in act['name']
and 'Europe without Switzerland' in act['location'] ][0]

ei_electricity=[act for act in ei if 'market for electricity, medium' in act['name']][0]

bio=bd.Database('ecoinvent-3.11-biosphere')
water_bio=bio.get('51254820-3456-4373-b7b4-056cf7b16e01')

Then, the datasets are assigned to the technosphere flows and the impact categories are defined for the impact calculation.

my_interface.methods=[('ecoinvent-3.11',  'EF v3.1',  'climate change',  'global warming potential (GWP100)')]

my_interface.add_dataset('steam generation', ei_steam)
my_interface.add_dataset('electricity grid',ei_electricity)
my_interface.add_dataset('electricity substitution',ei_electricity)

my_interface.add_dataset('steam leak',water_bio)

After that, the LCA calculation can be executed or the data exported to a brightway25 database:

my_interface.calculate_background_impact()
my_interface.calculate_impact()
code= my_interface.export_to_bw()

The result can be printed by:

my_interface.impact_allocated

This returns a dictionary containing the impact scores for all defined impact categories refered to one megajoule of heat transferred to the process.

{('ecoinvent-3.10',
'EF v3.1',
'climate change',
'global warming potential (GWP100)'): {'distributed steam': 0.15,
'network steam': 2.5}}

Substitution is configured by default. To switch to allocation, the electricity flow needs to be set to functional, and the target to None:

my_model.set_flow_attr('electricity substitution', 'target', None)
my_model.set_flow_attr('electricity substitution', 'functional',True )

my_interface.calculate_impact()