I have a case where I run a climate model using historic emissions, and then in 2015 it switches on to use emissions calculated by an IAM component. When I couple these together (so the shorter IAM emissions component provides inputs to the longer climate components starting in 2015), I get the following error: ERROR: Cannot add two components of the same name (ConnectorComp1). As far as I can tell, there are no components with the same name.
I attached a toy model that reproduces the error below. If you replace one of the connect_param!(...) lines with set_param(...) and just provide some exogenous data, it will run fine (i.e. it only errors when both connections are created).
using Mimi
# A longer CH4 cycle component that runs for 20 periods.
@defcomp ch4_cycle begin
ch4_emiss = Parameter(index=[time])
ch4_conc = Variable(index=[time])
function run_timestep(p, v, d, t)
if is_first(t)
v.ch4_conc[t] = 720.0
else
v.ch4_conc[t] = v.ch4_conc[t-1] + 0.5 * p.ch4_emiss[t]
end
end
end
# A longer CO2 cycle component that runs for 20 periods.
@defcomp co2_cycle begin
co2_emiss = Parameter(index=[time])
co2_conc = Variable(index=[time])
function run_timestep(p, v, d, t)
if is_first(t)
v.co2_conc[t] = 278.0
else
v.co2_conc[t] = v.co2_conc[t-1] + 0.1 * p.co2_emiss[t]
end
end
end
# A shorter emissions component that switches on in period 15.
@defcomp emissions begin
gdp = Parameter(index=[time])
co2_emiss = Variable(index=[time])
ch4_emiss = Variable(index=[time])
function run_timestep(p, v, d, t)
v.co2_emiss[t] = 0.25 * p.gdp[t]
v.ch4_emiss[t] = 0.1 * p.gdp[t]
end
end
# Create the model for 20 time steps.
m = Model()
set_dimension!(m, :time, 20)
# Add components (emissions turn on in period 15).
add_comp!(m, emissions; first=15)
add_comp!(m, co2_cycle)
add_comp!(m, ch4_cycle)
# Set exogenous gdp scenario for periods 15-20 in emissions component.
set_param!(m, :emissions, :gdp, ones(6) .* 100)
# Create component connections (with backup CO2 and CH4 emissions data for periods 1-15)
backup_ch4_data = ones(20) .* 15
backup_co2_data = ones(20) .* 5
connect_param!(m, :ch4_cycle => :ch4_emiss, :emissions => :ch4_emiss, backup_ch4_data)
connect_param!(m, :co2_cycle => :co2_emiss, :emissions => :co2_emiss, backup_co2_data)
run(m)