Homework
6 Oct. 2013
Note: For some of the problems, marked by *, not all the required information is provided
explicitly. That is on purpose, to oblige the student to search for data or make subjective
choices, just like in the real world. The student should indicate the source of the data and
justify the choices.
Life table data for the EU are provided in file LifetableEU.xlsx.
A request for the instructors: inventing good problems for homework and term papers is not
easy. If you can suggest new or better ones, please send me an email to
[email protected]
Likewise, please notify me if you find an error in the book or in the solutions to the
homework.
A. Topics for projects/papers............................................................................................. 1
Discussion questions, mostly at end of course: .......................................................... 2
Ch 1. Introduction.................................................................................................................. 3
Ch 2. Tools .............................................................................................................................. 4
Ch 3. Health ............................................................................................................................. 5
Ch 4: Buildings....................................................................................................................... 7
Ch 5: Agriculture ................................................................................................................... 7
Ch 6: Other impacts .............................................................................................................. 8
Ch 7: Atmospheric dispersion ........................................................................................... 8
Ch 8: Multimedia .................................................................................................................... 9
Ch 9: Economics ................................................................................................................... 9
Ch 10: Climate change ....................................................................................................... 10
Ch 11: Uncertainty............................................................................................................... 10
Ch 12: Results €/kg ............................................................................................................. 11
Ch 13: power ......................................................................................................................... 12
Ch 14: Waste Treatment .................................................................................................... 12
Ch 15: Transport .................................................................................................................. 13
A. Topics for projects/papers
A1*. Estimate your own GHG emissions per year, with breakdown by main categories:
 Electricity (other than heating and cooling),
 heating and cooling,
 transport,
 food,
 purchased goods,
 other.
Since your lifestyle and consumption patterns are likely to change, estimate also what your
GHG budget will look like ten years from now. What are the corresponding costs of a carbon
tax and which consumption items would you change if there were a carbon tax of $30/tCO2,eq,
or of $100/tCO2,eq?
There are quite a few carbon footprint websites. These two are particularly comprehensive
and well documented:
i) http://www.co2list.org
where you can download carbons.xls, a file with very detailed information of GHG emissions
from most activities and products
ii) http://coolclimate.berkeley.edu/carboncalculator
This project could be expanded by including the emissions of PM, SO2 and NOx, as well as
the corresponding damage costs. In that case it should be done by teams of 2 students. If the
class is sufficiently small, a final session with oral presentations would be interesting.
A2*. Carry out a social cost comparison of gasoline fueled cars and electric cars.
A3*. Compare the incineration of MSW with energy recovery in the form of electricity with
the alternative of separating the combustible fraction as refuse derived fuel, to be burned in
coal-fired power plants, the rest of the waste going to landfill.
A4*. Estimate the contribution of all-cause mortality to the damage cost of Cd, based on
Tellez-Plaze [2013] (this should include a lifetable calculation of the life expectancy loss).
How much would this increase the cost of waste incineration and of electricity from coal?
Helpful info: to relate intake to urinary Cd concentration, assume
urinary Cd/Cd dose = 0.022 (U-μgCd/gcreatinine)/(μgCd/day), averaged over men and women.
A5*. Compare the environmental impacts of grocery bags made of paper with bags made of
plastic, taking into account all the relevant upstream and downstream impacts. Consider how
various alternatives of the upstream and downstream activities may change the results.
Comment on the way competing industries may try to bias the analysis in their favor.
A6*. Compare the environmental impacts of paper towels and electric dryers in public
restrooms, taking into account all the significant upstream and downstream impacts. Consider
how various alternatives of the upstream and downstream activities may change the results.
Comment on the way competing industries may try to bias the analysis in their favor.
A7*. Compare organic and conventional agriculture, in terms of health and environmental
benefits. Do you think the higher cost of organic agriculture is worth the benefits?
Discussion questions, mostly at end of course:
D1. When you began reading this book, you were likely to have ideas about environmental
policies to pursue. How have those views changed? Do you have more confidence in the views
you hold now or are you less confident that those views are correct?
D2. Is our environment cleaner or dirtier than in the past? What is the outlook for the future?
This has no simple universal answer; rather you have to look at specific periods and places, e.g.
ancient Rome, London at the end of the Dark Age, cities during the industrial revolution, Los
Angeles during the nineteen sixties, cities in China now. Get air quality data for the city where
you live.
D3. What is the outlook for our environment in the future? There are optimists (“boomsters”) and
pessimists (“doomsters”). Present arguments for each of these positions, and draw your own
conclusions.
D4. Suppose that you are considering job offers in two or more locations. How important will
environmental quality be in your decision? All else being equal, how much wage
compensation would be necessary to get you to move to a polluted city with significant health
impacts (shortening your life expectancy by six months)? Would the answer to that question
change if because of dominant wind patterns there are sufficiently clean areas in or near that
city?
D5. In terms of health damage costs it would be preferable to locate a polluting factory in the
desert areas of the Southwest of the USA rather than the densely populated areas of the coasts.
What other considerations should be taken into account? Should the environmental regulations be
the same in the entire country?
D6. Consider an industrial activity that brings great economic benefit, but at the risk of
permanently polluting a local aquifer. Suppose that a careful and thorough cost-benefit analysis of
such an activity finds that the environmental damages are negligible, except for health impacts if
water from the aquifer is used for the water supply; however, the cost of providing clean water
from other sources would be small compared to the profit of the activity. (This is a hypothetical
and extreme example, although fracking would come close if the emission of CH 4 and other air
pollutants can be kept sufficiently low). Should the activity be allowed?
D7. Discuss the equity implications of various environmental policies, for instance a carbon tax or
a tax on the pollutants emitted by power plants and industrial installations. What could or should
be done to alleviate or avoid the resulting inequity? Can you think of environmental policies that
are not regressive (in the sense of taking a larger percentage of disposable income from the poor
than from the rich)?
D8. What changes could you make, in your home or your life style, to improve the
environment? Quantify the benefits and discuss the cost and/or disadvantages.
B. Homework problems
Ch 1. Introduction
H1.1. Consider a factory that currently emits E0 = 100 kg/yr of a pollutant into a river; the
pollution affects n people and the damage cost is Cdam(E) = n b E with
b = $1.0/kg/person/yr. Abatement for reducing the emissions to levels E below E0 would cost
Cab(E) = a (E0/E – 1) for E < E0 with a = $10,000/yr. Find the optimal emission level Eopt and
the corresponding Cab(Eopt) and Cdam(Eopt) for n = 100, n = 1000 and n = 10,000. What
happens when n is less than 100?
H1.2. Consider several situations and policy options for dealing with the pollution problem of
H1.1.
(i) The government imposes a pollution tax equal to the marginal damage and gives the
proceeds to the victims of the pollution.
(ii) The government does nothing, and will not even enact any laws to protect people from
pollution. But suppose in this case the victims of the pollution know what the damage is and
they find it easy and effortless to organize in order to pay the factory to reduce the emissions.
(iii) Consider a world where all factories emit pollution with the same damage costs (same
cost per kg/person/yr and same number of victims n > 100 per factory) and the same
abatement costs as in H1.1; furthermore, all consumers and none of the factory owners are
victims. The factory owners pass all their abatement costs and/or pollution taxes on via
increased prices for the consumers of their products.
a) What emission level minimizes the loss of the victims under policy (i) and under policy
(ii)? Comment: this is an illustration of the Coase theorem which says that in the limit were
the transaction costs are negligible the optimal level of the externality will be reached even
without government intervention. In practice the transaction costs would be prohibitive for
almost all pollution problems.
b) Compare who pays how much under the policies i) and ii).
c) Who pays how much in situation iii)?
d) Would the answer to b) change if the factory owners were also victims of their pollution?
e) Would the answer to b) change if different victims suffered different damage costs?
f) To what extent do the conclusions of part c) also hold for greenhouse gases?
H1.3. Which of the following situations involve technological externalities, which involve
pecuniary externalities?
a) Some of the corn harvest is shifted from food to producing ethanol for cars, causing the
price of food to increase.
b) A waste treatment facility is built near a residential area, causing significant nuisance for
the residents due to the increased truck traffic.
c) Drinking water is polluted by fracking for gas production.
d) A reservoir is built for hydro power and it creates new opportunities for swimming and
boating.
e) Increased demand for oil in China drives up the price of gasoline in Europe.
Ch 2. Tools
H2.1. Compare the CO2 emissions due to heating a house with those from its construction.
Consider a house made of brick and cement and assume that the only significant CO 2
emission from its construction is due to the production of brick and cement, at an average of
0.2 kgCO2/kg of material. The house is a box with length = width = 12m and height = 2.5 m.
For the mass of brick and cement assume a thickness 0.2 m for both the floor slab and each of
the walls, with density 2,000 kg/m3. For the heating demand assume a heat loss of 160 W/K
and 2,000 degree.days. The heating system uses natural gas with efficiency 0.9. The
combustion of natural gas emits 50 kgCO2/GJ. The “embedded” CO2 in the house is equal to
how many years of emissions from the heating system?
In the following problems “Define the boundaries for the analysis” means specifying which
effects should be taken into account.
H2.2. There have been many debates about the choice of bags for grocery shopping: should
they be made of paper or of plastic? Define the boundaries for the analysis of this issue.
H2.3. Define the boundaries for an LCA of ethanol fuel production from corn.
H2.4. Define the boundaries for a social cost comparison of gasoline fueled cars and electric
cars.
H2.5. Draw the system boundaries for the recycling of paper, comparing two possible sources
of fresh paper: dedicated tree farms and natural forest. Now include within the system power
plants based on combustion of wood. Comment on the desirability of paper recycling for each
of these cases.
H2.6*. These two LCA inventory databases are free of charge:
i)
the
European
reference
Life-Cycle
Database
(ELCD
3.0)
at
http://elcd.jrc.ec.europa.eu/ELCD3/
ii) the U.S. Life Cycle Inventory Database of NREL at http://www.nrel.gov/lci/
Use these databases and try to find the emissions to air of PM10, NO2, SO2, CO2, As, Cd, Hg
and Pb per kg of aluminum (to search ELCD, use the English spelling “aluminium”). Use
only the emissions listed under Outputs.
Calculate the damage cost per kg of aluminum by combining the emissions with the damage
costs per kg of pollutant of Section 12.2.1:
PM10
16.3 €/kg
NO2
7.1 €/kg
SO2
6.8 €/kg
CO2
0.021 €/kg
As
529.6 €/kg
Cd
83.7 €/kg
Hg
8000 €/kg
Pb
278.3 €/kg
Note: at the time of this writing (August 2013) there were inventories for several types of
these metals and the presentation was different between the databases, so you may get several
different results. Compare and comment.
Ch 3. Health
H3.1. The air quality standards for the EU set a limit of 40 g/m3 for the annual mean PM10
concentration. What is the number of cases of chronic bronchitis per year at this concentration
in a city of 1 million?
H3.2. The annual mean O3 concentration in Paris is about 36 μg/m3 and in the adjacent rural
zones it is about 50 μg/m3. How many respiratory hospital admissions are due to O3 if the
ERF is linear without threshold? Assume that the daily maximum 8-hr moving average is
about 50% higher than the annual average, and assume that 5 million are exposed to the lower
urban concentration and 5 million to the higher concentration of the surrounding areas.
H3.3*. At an altitude of 10,000 m the cosmic radiation dose is about 5 Sv/hr.
a) What is the dose due to a round trip transatlantic flight (total duration 15 hr)?
b) What is the dose for pilots and flight attendants who make 100 such round trips per year,
and how does is compare with typical background doses?
c) What is the mortality impact for a single round trip transatlantic flight and for someone
who makes 100 such round trips per year for 40 years?
d*) What are the corresponding costs if premature deaths are valued at 3 M€? How do these
costs of the flight crew compare with the price of a ticket?
H.3.4. a) Use the data LifetableEU.xlsx to calculate the life expectancy LE for the EU.
Since the mortality data go only to age 84, use the Gompertz formula to fit the data from age
30 to 84 and use that fit to estimate the mortality (x) up to age 110.
b) Show that LE decreases only by a factor of about RR/7 when (x) increases by a small
amount RR.
H3.5. In recent years many epidemiological studies on the effects of Cd have been carried
out, and the results imply that the damage cost is much larger than the estimate by ExternE
[2008] which is based only on lung cancer from inhalation of Cd. There are more endpoints,
and the much larger ingestion dose is toxic. In the following problems you will derive and
apply an ERF for all-cause mortality.
Most epidemiological studies use urinary Cd, measured as μgCd/gcreatinine, as biomarker for Cd
exposure. For the relation between total Cd intake and urinary Cd you can assume
urinary Cd/intake = 0.022 (U-μgCd/gcreatinine)/(μgCd/day),
based on Sirot et al [2008] and Olsson et al [2002].
Tellez-Plaza et al [2013] find that the all-cause mortality increases by a factor of
RR = 1.52 (CI 1.00-2.10)
when the urinary Cd concentration increases
from 0.14 U-μgCd/gcreatinine to 0.57 U-μgCd/gcreatinine.
a) Use the lifetable calculation of problem H3.4 to find the LE loss corresponding to this RR.
b)
RR/exposure = 1.21/(U-μgCd/gcreatinine).
(4.6)
H3.5. For the relation between Cd intake and urinary Cd assume a ratio of
urinary Cd/Cd dose = 0.022 (U-μgCd/gcreatinine)/(μgCd/day), averaged over men and women,
based on data of Sirot et al (2008) and Olson et al (2002). Using the results of H3.4 calculate
the LE loss due to the Cd content of tuna for someone who eats 120 g of tuna per week.
Sirot V, Samieri C, Volatier JL, Leblanc JC. 2008. “Cadmium dietary intake and biomarker
data in French high seafood consumers.” J Expo Sci Environ Epidemiol. 2008
Jul;18(4):400-9. Epub 2007 Sep 19.
Olsson IM, Bensryd I, Lundh T, Ottosson H, Skerfving S, Oskarsson A. 2002. “Cadmium in
blood and urine--impact of sex, age, dietary intake, iron status, and former smoking-association of renal effects.” Environ Health Perspect. 2002 Dec;110(12):1185-90.
H3.7*. Measurements by Storelli et al [2010] of toxic metal concentrations in tuna found the
following results (ND = not detected), in g/g wet weight:
Average
Range
Hg
0.61
0.07–1.76
Pb
0.07
ND-0.33
Cd
0.01
ND-0.03
According to the ERFs of Chapter 3, ingestion Cd has no effect, Pb affects only children and
Hg only pregnant women; the latter effects that can be avoided if the respective groups do not
eat tuna. However, more recent evidence indicates that ingestion of these metals has serious
effects on everybody, especially increased mortality. We estimate the following ERF slopes:
for Hg: 0.066 YOLL/(microgHg/day) based on Rice et al [2010],
for Pb: 0.005 YOLL/(microgPb/day) based on Menke et al [2006],
for Cd: 0.003 YOLL/(microgCd/day) based on Tellez-Plaza et al [2013].
a) Calculate the dose of toxic metals from eating 120 g of this tuna per week, and estimate the
resulting health impacts.
b*) Are these effects a reason to stop eating tuna?
References:
Storelli MM, Barone G, Cuttone G, Giungato D, Garofalo R. (2010). “Occurrence of toxic
metals (Hg, Cd and Pb) in fresh and canned tuna: public health implications.” Food
Chem Toxicol. 2010 Nov;48(11):3167-70.
Menke A, Muntner P, Batuman V, Silbergeld EK, Guallar E. 2006. “Blood Lead Below 0.48
Circulation. Vol.114, 1388–
1394.
Rice GE, Hammitt JK, Evans JS. 2010. A probabilistic characterization of the health benefits
of reducing methyl mercury intake in the United States. Environ Sci Technol 44:5126–
5224.
Tellez-Plaza M, Navas-Acien A, Menke A, Crainiceanu CM,5 Pastor-Barriuso R, Guallar
E.2012. “Cadmium Exposure and All-Cause and Cardiovascular Mortality in the U.S.
General Population”. Environmental Health Perspectives, Vol. 120 (7), 1017-1022.
Ch 4: Buildings
H4.1.* Obtain a rough order of magnitude estimate for air pollution damage to buildings by
making the following assumptions:
i) in the absence of pollution the exterior surfaces of buildings would need to be repaired (by
cleaning, painting, resurfacing and the like) once very 50 years and with the current pollution
in the EU27 the frequency of such repairs is doubled;
ii) the average wall area per person is 40 m2;
iii) the average repair cost is 20 €/m2.
Compare with the health costs due to PM2.5, using Eq.12.2a for the cost per exposure and
assuming an average concentration of 20 g/m3. Is the small contribution of buildings to the
damage cost of pollution plausible?
Ch 5: Agriculture
H5.1. Italy produces about 1.5 million tonnes of rice per year, mostly in the Po region where
summer time ozone levels are very high, with AOT40 above 13.5 ppm·hr according to the
ozone map of the European Environment Agency [http://www.eea.europa.eu/data-andmaps/figures/ozone-aot40-for-crops-2010]. Suppose the current level is 15 ppm·hr. How
much would the production gain be worth if the AOT40 level could be brought down to levels
of Northern Europe, about 6 ppm·hr?
Ch 6: Other impacts
H6.1. The incidence of myocardial infarction is approximately 4 per 1000 per year, and about
5% are fatal. Estimate the contribution to the cost of a daytime noise level of Lday = 75 dB
(compared to a quiet environment, < 55 dB), approximating RR by OR and valuing fatal cases
at 1.5 M€, nonfatal cases at 2000 €.
Ch 7: Atmospheric dispersion
H7.1. Plot the ground level concentration of the Gaussian plume of Eq.7.8 for the six stability
categories, with the plume parameters of Briggs and Gifford for rural dispersion (Eq.7.20),
assuming no pollutant decay or depletion. Use Eq.7.13 for S(r,z), setting Rg and Rm = 1. Take
a stack height he = 100 m without plume rise, an emission rate of 1000 t/yr, and assume a
constant hmix = 500 m. Beyond what x can the vertical distribution be considered uniform?
H7.2. Calculate the plume rise for flue gases emitted with exhaust speed ws = 10 m/s and
temperature Ts = 200 C from a stack of diameter ds = 5 m and height hs = 100 m, for each
Pasquill class when the ambient temperature is Ta = 20 C and the wind speed at 10 m height is
u = 10 m/s (use the wind profile exponent EPA (1995) rural of Table 7.4). Plot as function of
the downwind distance x.
H7.3. Using the parameters and the final plume rise hmax for Pasquill class B of problem
H7.2 as reference values, vary exhaust speed ws, exhaust temperature Ts, stack diameter ds,
and stack height hs. Plot in a single graph as final plume rise hmax versus x/xref and x
represents the input parameters. Consider the following ranges for the input parameters: ws
from 0 to 20 m, Ts from 20 to 400 C, ds from 0.1 to 10 m, hs from 0 to 200 m.
H7.4. Is plume rise significant (for damage cost calculations) for exhaust of passenger cars?
Of trucks with vertical exhaust pipe at roof level (assume exhaust speed 15 m/s, temperature
200 C)?
H7.5.* The annual average PM10 concentration in Paris is approx. 25 g/m3. Estimate the dry
deposition flux of PM10, if the dry deposition velocity is 0.01 m/s. Make a rough guess about
the density of the deposited particulate matter to estimate how thick a layer would be
deposited during one year, if it were not washed or blown away by the rain and wind.
H7.6. Use the simple regional model of Eq.7.38 to estimate at what distance r from the source
the concentration is reduced
(a) by a factor 0.5, and by a factor 0.1
relative to the value at r = 50 km. Assume mixing layer height hmix = 600 m, depletion
velocity kp = 0.01 m/s and wind speed u = 5 m/s. How do the answers change if wind speed =
10 m/s?
b) Assuming uniform receptor density  and linear exposure-response function, plot the
fraction of the total impact that occurs within a radius R of the source. How large a range of
the analysis is needed to include 95% of the total impact?
H7.7. Calculate the intake fraction for automotive emissions in Stuttgart, Germany.
For the following problems assume that nitrates from NOx emissions are PM10 and sulfates
PM2.5, and assume the following for the cost of exposure (sum of the SERF,i Pi):
sum of the SERF,i Pi = 38.8 (€/yr)/(person.µg/m3) for PM2.5
and
sum of the SERF,i Pi = 25.6 (€/yr)/(person.µg/m3) for PM10.
H7.8. Use the UWM and Table 7.8 to calculate the health damage cost per kg of pollutant for
industrial emissions (stacks of h = 50 m) of PM2.5, PM10, sulfates from SO2, and nitrates from
NOx in the Northeast of the USA (regional population density 122 persons/km).
H7.9. Use the UWM to calculate the health damage cost per kg of pollutant for PM2.5 and for
NOx emitted by cars in Prague. Compare with the damage costs if the same pollutants are
emitted by industrial sources in the Czech Republic with stacks of about h = 50 m.
Ch 8: Multimedia
H8.1. According the data in WHO [2001] about 25% of the As in food is inorganic. How
much larger would the damage cost of Table 8.5 be if all ingested inorganic As is equally
carcinogenic?
Reference: WHO 2001. Arsenic and Arsenic Compounds. Environmental Health Criteria 224,
updated in 2004. World Health Organization.
http://www.inchem.org/documents/ehc/ehc/ehc224.htm#1.2
Ch 9: Economics
H9.1. Even though the damage cost of CO2 emitted today varies from year to year in a more
complicated manner, consider as very rough approximation two cases
a) a stream of constant annual costs for the next 200 years,
b) annual costs that increase at a rate of 1% per year during 200 years,
and zero damage thereafter.
Compare the total cost for two choices of the discount rate: 1% (without pure time preference)
and 4% (with pure time preference), for these two cases.
H9.2*. As an alternative valuation of restricted activity days, attribute the GDP/capita to the
number of working days/yr of the entire population. Estimate the latter by finding data for the
employment-to-population ratio (a standard data set collected by OECD).
Compare your result with the value 295 €/day chosen by ExternE [2008] (see Table 12.3) and
discuss.
H9.3*. Compare the cost of hospital admissions assumed by NRC [2010] with the analogous
costs of ExternE [2008]. Then scale the NRC numbers according to the magnitude of general
health costs (GDP per capita and % of GDP spent on health) between The USA and the EU.
Comment.
H9.4*. Answer the WTP question of the VOLY questionnaire of Section 9.3.2. Calculate the
resulting VOLY if everybody declared the same WTP as you. Comment on the reasons for
your WTP. How do you think your WTP might change as you grow older?
H9.5*. Some economists have tried to estimate the value of clean air by comparing the price
of housing between polluted and less polluted areas. What goods are taken into account in
such analysis? How could the results be used, assuming that the influence of all confounders
has been eliminated? Would the contribution of such results be large or small compared to the
cost of health impacts of air pollution?
Ch 10: Climate change
H10.1. Worldwide nitrogen fertilizer use was around 150 million tonnes (as N content) in
2010. Use Section 5.3.3 to estimate the resulting greenhouse gas emissions, in tCO2eq/yr.
H10.2*. Make your own prediction of the total worldwide GHG emissions in 2030, if there is
no abatement. Estimate how much lower the emissions would be if all the abatement potential
in Fig.10.15 were implemented
a) if the damage cost is $30/tCO2eq,
b) if the damage cost is $85/tCO2eq.
H10.3*. Make a rough estimate of the sea level rise via thermal expansion for a doubling of
atmospheric CO2, by assuming that the temperature rise of the ocean is equivalent to a
uniform increase in a layer of 50 m depth, the current average temperature being 12 C.
Discuss some of the limitations of this simple model.
For the following problem use the file carbons.xls, which can be downloaded from the carbon
footprint calculator http://www.co2list.org
H10.4*. a) Estimate the annual cost of the following items
i)
Driving a car 10,000 km/yr
ii)
Eating beef 5 times a week
iii)
Running the air conditioner 500 hr/yr
b) How much would these costs increase if there were a carbon tax of $30/tCO2eq and of
$85/tCO2eq, respectively?
c) how much do you think people would reduce the consumption of these items emissions if
there were such a tax?
Ch 11: Uncertainty
H11.1. Calculate mean, standard deviation, geometric mean and geometric standard deviation
for this set of points: {1, 2, 3, 4, 5,6,7}. What would happen if the first number were replaced
by 0 or by -1?
H11.2. Plot the lognormal probability density function with g = 1 and g = 2, and show the
68% and the 95% confidence intervals. Calculate the ordinary mean  and the ordinary
standard deviation .
H11.3. a) Plot the lognormal probability distribution with g = 1 and g = 1.1 and calculate
the ordinary mean  and the ordinary standard deviation .
b) On the same plot show the probability density function of a normal distribution with this 
and .
c) How do the normal and lognormal distributions compare in the limit g 1?
H11.4. Consider a pollution control measure whose cost C has a normal distribution with
mean 1 M€ and standard deviation 0.2 M€.
a) The benefit B has a lognormal distribution with geometric mean 1 M€ and geometric
standard deviation 3. Calculate the distribution of the net benefit B – C. What is the
probability that B < C?
b) How do the results change if the geometric standard deviation of B were only 1.5?
c) If it is not feasible to improve the assessment of costs and benefits, should the measure be
implemented (if g = 3, if g = 1.5)?
H11.5*. Make a simple estimate of the uncertainty of the damage cost per kg of Cr emitted by
waste incinerators if the only impact is cancer due to the inhalation of Cr-VI. Assume that the
RR for cancer risk due to Cr-VI has a geometric standard deviation of 2 and that the
percentage of Cr-VI in the emitted Cr is 20% with 68% confidence interval of 10 to 30%.
How much would the result change if the percentage of Cr-VI were known exactly?
H11.6. Use the equations of Section 11.4.2 to estimate g and g for the sum of lognormally
distributed impacts with the g and g of Fig.11.9. Compare with the corresponding values for
the lognormal fits.
Ch 12: Results €/kg
H12.1. Ozone concentrations in Italy are very high, with SOMO35 levels of about 8000
(g/m3)·day.
a) How large are the resulting annual health costs, per person and for the country?
b) Compare with the cost of PM2.5, if the average PM2.5 concentration is 20 g/m3.
c) Compare with the total health expenditures of Italy, if the latter are 9% of GDP.
H12.2. Use the UWM with the depletion velocities of Table 7.8, together with a population
density of 112 person/km2, to estimate the damage cost of PM2.5 and PM10 emissions in the
EU27, assuming that PM10 emissions have a composition 60% PM2.5 and 40% PMco, and
taking the depletion velocity of PMco equal to that of PM10. Compare with Fig.12.1.
H12.3. Use the UWM to estimate the damage cost of PM2.5 and PM10 emissions in several
regions of the USA: Colorado (14 pers/km2), the Northeast (122 pers/km2), and California
(79 pers/km2). Make the same assumptions as for H12.1 and use the depletion velocities of
Table 7.8 for the USA. Compare with Table 12.5.
H12.4.* Starting with the numbers in Section 12.1.3 try to estimate the health damage cost
per person and life expectancy loss in Beijing where the average PM10 concentration officially
reported in 2010 was 121 g/m3. How should the cost components be adjusted from EU to
China?
Ch 13: power
H13.1.* Compare the cost of an incandescent light bulb with a compact fluorescent one, for
an individual and for society.
a) Consider only the damage costs of electricity production and neglect discounting.
b) Choose an appropriate discount rate and recalculate the results.
H13.2. The damage costs per kWh of Fig.13.7 do not include upstream impacts. But gas in
the USA is increasingly produced by “fracking”, with significant leakage to the atmosphere.
At what leakage rate do the greenhouse gas costs of electricity from gas become equal to
those of electricity from coal? You can assume the emission rates of Table 13.10 for gas from
conventional sources.
H13.3. Fig.13.7 does not provide a breakdown by pollutant. Estimate the contribution of SO2
by using the mean entries of Table 13.6. Since the weighting of power plants is different
between Fig.13.7 and Table 13.6, the total cost/kWh implied is different from Fig.13.7.
Rescale the contribution of each pollutant by the ratio of the respective totals.
a) Compare the damage cost of SO2 with the private cost of electricity.
b) How large would be the benefit, per kWh, if the SO2 emissions per kWh would be brought
down to the levels in the EU?
H13.4.* Make your own assessment of the risks and damage costs of nuclear power and
compare with alternatives.
H13.5*. Compare the mortality impact of electricity from coal on the general public with the
mortality impact on workers. As approximation you can assume that the entire damage cost of
SO2 and NOx calculated by ExternE is due to health, assuming that the nitrates and sulfates
are PM10.
H13.6*. Estimate the health damage cost per kWh of electricity from coal in the USA and in
the EU, using the same model (the UWM with the ERFs and unit costs of Table 12.3).
Assume that sulfates are PM2.5 and nitrates PM10; neglect O3.Compare with the results of
NRC [2010].
Ch 14: Waste Treatment
H14.1*. Waste incineration can be considered a source of renewable energy.
What fraction of our total electricity demand could be supplied by incineration of municipal
solid waste?
H14.2*. Find emissions data for incinerators of municipal solid waste in the USA and
estimate the damage costs per tonne of waste.
H14.3*. Use the results of H2.6 for the emission of PM10, NOx, SO2, CO2, As, Cd, Hg and
Pb per kg of aluminum, together with the recovery rates of Table 14.5, to calculate the
benefits due to aluminum recovery from incinerators. Comment on the result.
H14.4. Calculate the reduction of damage costs due to energy recovery from incinerators of
municipal solid waste if the energy is used for process heat or a district heating system, with
sufficient baseload so no heat is wasted. Assume that this heat displaces natural gas, with
emissions
NO2: 0.1 g/kWh,t,
GHG: 220 g/kWh,t,
other emissions being negligible.
These NO2 emissions are equal to what's implied by the limit values of the LPC Directive of
2001 of the EU, assuming typical air flow rates). If the actual NO2 emissions are significantly
lower, would that have a strong effect on the benefit of energy recovery?
H14.5. Calculate the reduction of damage costs due to energy recovery from incinerators of
municipal solid waste in the EU if the energy is used for producing electricity. Assume that
the electricity would have been produced by coal and natural gas, in equal parts.
H14.6. Despite the existence of the E-PRTR database (http://prtr.ec.europa.eu) for the
reporting of emissions, the measuring and reporting of emissions data for toxic metals by
incinerators in the EU leaves much to be desired. Only the very largest installations are
required to measure and report results, and that only for a few metals; the corresponding
quantity of waste is not reported. For the year 2011 the three largest incinerators of Paris
report only the following emissions of toxic metals (the numbers for the quantity of waste are
from a different source):
twaste
Cd, kg
Hg, kg
Pb kg
St.Ouen
618,000
Yvry
680,000
16.1
37
Issy-les-Moulineaux
502,000
47.2
216
Assuming these numbers to be representative, calculate the contribution of Cd, Hg and Pb to
the damage cost per twaste, for the costs per kg of pollutant of ExternE [2008], as well as for a
more recent assessment by Nedellec and Rabl [2013] who find 52,000 €/kgCD, 8,600 €/kgHg
and 14,425 €/kgPb.
Reference: Nedellec V and Rabl A. 2013. “Projet AMESTIS: Amélioration de l’estimation des
impacts sanitaires des déchets et de leur évaluation monétaire” (Project AMESTIS:
Improving the estimation of health impacts of waste and their monetary valuation). Final
Report to ADEME, September 2013.
Ch 15: Transport
H15.1. During the 20th century most cars used leaded gasoline.
According to http://yosemite.epa.gov/R10/airpage.nsf/webpage/Leaded+Gas+Phaseout
“regular” (i.e. leaded) gasoline contained about 1 gPb/L.
a) How large would the damage cost per km of typical passenger cars be if the gasoline still
contained Pb at this level? Compare with the air pollution damage cost in Table 15.3.
b) Does this result vary significantly with the location where the car is driven?
H15.2. Consider a EURO2 diesel bus whose PM2.5 emissions are 0.70 g/km.
a) Estimate the resulting damage cost per km in typical large cities of Western Europe.
b) What is the annual damage cost if the bus drives 25000 km/yr? A particle filter removes
about 95% of the PM2.5 emissions; it costs 4000 €.
Is a particle filter for the bus justified by a cost-benefit analysis in these cities? How about for
rural driving?
To answer this question you may assume that a present value analysis with social discount
rate (approx. 5%) and life time 10 years is equivalent to 7.5 years of utilization with zero
discount rate.
H15.3.* Compare CO2 emissions of air plane and of high speed trains if the electricity for the
trains comes from nuclear, from natural gas combined cycle or from condensing coal plants.
For the high speed trains assume 16.0 kWhe/vkm and an occupancy of 400 passengers per
train (this technology with speeds of 300 to 350 km/hr uses special tracks and is different
from the tilting train technology of Table 15.13 which runs on conventional tracks with
speeds under about 220 km/hr).
H15.4. A recent study of high speed rail for California has compared trains, cars and plane for
the travel between Northern and Southern California: Chester, M and Horvath, A. 2010.
“Life-cycle assessment of high-speed rail: the case of California”. Environ. Res. Lett. 5
(2010) 014003 (8pp).
Look
at
the
paper
(downloadable
from
http://iopscience.iop.org/17489326/5/1/014003?fromSearchPage=true).
The second part of Fig.1 shows a breakdown of CO2 emissions by stage of the respective
transport systems. The occupancy scenarios are rather extreme, especially the low occupancy
scenario for the train with 120 passengers (for a capacity of 1200) and the high occupancy
scenario of 5 passengers for the car; but that highlights the importance of high occupancy to
make trains financially and environmentally viable.
How do the CO2 emissions from the construction of the road or rail infrastructure compare
with those from the utilization, for cars and for high speed rail?