Class: AutomobileFuel

Inherits:
ActiveRecord::Base
  • Object
show all
Defined in:
lib/earth/automobile/automobile_fuel.rb

Constant Summary collapse

CODES = 
{
  :electricity => 'El',
  :diesel => 'D'
}

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.fallback_blend_portion ⇒ Object 



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# File 'lib/earth/automobile/automobile_fuel.rb', line 15

def fallback_blend_portion
  latest_year = AutomobileTypeFuelYear.maximum('year')
  gas_use = AutomobileTypeFuelYear.where(:year => latest_year, :fuel_common_name => 'gasoline').sum('fuel_consumption')
  diesel_use = AutomobileTypeFuelYear.where(:year => latest_year, :fuel_common_name => 'diesel').sum('fuel_consumption')
  diesel_use / (gas_use + diesel_use)
end

Instance Method Details

#annual_distance ⇒ Object

FIXME TODO should I run data miner on other classes we need? Fuel

> FuelYear

GreenhouseGas



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# File 'lib/earth/automobile/automobile_fuel.rb', line 49

def annual_distance # returns km
  scope = type_fuel_year_ages.any? ? type_fuel_year_ages : AutomobileTypeFuelYearAge
  scope.where(:year => scope.maximum('year')).weighted_average(:annual_distance, :weighted_by => :vehicles)
end

#ch4_emission_factor ⇒ Object

returns kg co2e / litre



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# File 'lib/earth/automobile/automobile_fuel.rb', line 75

def ch4_emission_factor # returns kg co2e / litre
  latest_type_fuel_years.weighted_average(:ch4_emission_factor, :weighted_by => :total_travel) * GreenhouseGas[:ch4].global_warming_potential
end

#co2_biogenic_emission_factor ⇒ Object

returns kg co2 / litre



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# File 'lib/earth/automobile/automobile_fuel.rb', line 62

def co2_biogenic_emission_factor # returns kg co2 / litre
  if blend_fuel.present?
    (base_fuel.co2_biogenic_emission_factor * (1 - blend_portion)) + (blend_fuel.co2_biogenic_emission_factor * blend_portion)
  else
    base_fuel.co2_biogenic_emission_factor
  end
end

#co2_emission_factor ⇒ Object

returns kg co2 / litre



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# File 'lib/earth/automobile/automobile_fuel.rb', line 54

def co2_emission_factor # returns kg co2 / litre
  if blend_fuel.present?
    (base_fuel.co2_emission_factor * (1 - blend_portion)) + (blend_fuel.co2_emission_factor * blend_portion)
  else
    base_fuel.co2_emission_factor
  end
end

#hfc_emission_factor ⇒ Object

returns kg co2e / litre (hfc emission factor is already in co2e)



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# File 'lib/earth/automobile/automobile_fuel.rb', line 83

def hfc_emission_factor # returns kg co2e / litre (hfc emission factor is already in co2e)
  latest_type_fuel_years.map do |type_fuel_year|
    type_fuel_year.total_travel * type_fuel_year.type_year.hfc_emission_factor
  end.sum / latest_type_fuel_years.sum('total_travel')
end

#latest_type_fuel_years ⇒ Object 



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# File 'lib/earth/automobile/automobile_fuel.rb', line 70

def latest_type_fuel_years
  scope = type_fuel_years.any? ? type_fuel_years : AutomobileTypeFuelYear
  scope.where(:year => scope.maximum('year'))
end

#n2o_emission_factor ⇒ Object

returns kg co2e / litre



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# File 'lib/earth/automobile/automobile_fuel.rb', line 79

def n2o_emission_factor # returns kg co2e / litre
  latest_type_fuel_years.weighted_average(:n2o_emission_factor, :weighted_by => :total_travel) * GreenhouseGas[:n2o].global_warming_potential
end