Effects of Urban Land-Use Regulations on Greenhouse Gas Emissions

Transcription

1 Effects of Urban Land-Use Regulations on Greenhouse Gas Emissions U.S. Green Building Council, Central Texas Chapter February 16, 2017 Dr. Benjamin D. Leibowicz Assistant Professor Graduate Program in Operations Research and Industrial Engineering The University of Texas at Austin

2 Why is This Linkage Important? 1. The world is rapidly and persistently urbanizing. By 2050, two-thirds of the global population will reside in cities. 2. With strong federal action against climate change unlikely, some individual cities will explore ways to reduce emissions using policy levers they control. 3. The built environment changes very slowly, so it s important to get it right. 1

3 Annual Household CO 2 Emissions (tons) Annual Household CO 2 Emissions Electricity Home Heating Public Transit Driving 5 0 Portland New York Austin Houston Metropolitan Statistical Area Source: Glaeser and Kahn (2010) 2

4 Is Texas Just Really Hot? 3

5 It s More Complicated Than That Source: Glaeser and Kahn (2010) 4

6 Explanations for CO 2 Variation Residential CO 2 Emissions - Climate - Home size - Building energy efficiency - Fuel mixes for electricity and heating Transportation CO 2 Emissions - Total travel - Mode shares - Composition of vehicle fleet * Income and price effects are embedded in most of these. 5

7 Explanations Strongly Linked to Urban Form Residential CO 2 Emissions - Climate - Home size - Building energy efficiency - Fuel mixes for electricity and heating Transportation CO 2 Emissions - Total travel - Mode shares - Composition of vehicle fleet 6

8 Urban Forms Portland New York Austin Houston 7

9 Urban Forms Portland New York Austin Houston 8

10 Urban Land-Use Regulations Traditional zoning rules - Floor area ratio (FAR) restriction Imposes an upper limit on the ratio of building floor area to the area of the lot Smart growth policies - Urban growth boundary (UGB) Prohibits urban development beyond a specified perimeter including the central city and close-in suburbs Any land-use regulation which affects urban form can have a large impact on GHG emissions 9

11 Portland FAR Restrictions 10

12 Portland UGB 11

13 Regulation-Induced Migration Types of Migration Central City FAR Restriction Inward Outward Inter-city Suburban FAR Restriction UGB 12

14 Land-use restrictions, often allegedly implemented for environmental reasons, may be having the ironic effect of moving development from low emissions places, like California, to high emissions places, like Texas. It is certainly possible that land-use restrictions are actually pushing people away from lower emission areas into higher emission areas. This topic seems to merit future research. Source: Glaeser and Kahn (2010) 13

15 Recent Study Develop a modeling framework to evaluate the effects of urban land-use regulations on GHG emissions Extends the monocentric city model from urban economics Urban form adjusts endogenously to regulation Represents two urban areas so that inter-city migration is captured, in addition to inward and outward migration Numerical simulations using empirical data for Portland and Houston 14

16 Model Structure Two equilibrium concepts - Economic equilibrium in the housing market - Spatial equilibrium in consumer utility Households maximize consumer utility - All workers commute to the city center - Households allocate non-commuting budget to housing and a composite good Housing producers maximize profit - Production function has capital and land inputs - Determine the density of housing 15

17 kg CO 2 per household roundtrip mile kg CO 2 per square foot housing CO 2 Emissions Annual household CO 2 emissions are a linear function of distance from the city center (transportation) and home size (residential) Transportation Residential Portland Houston 0 Portland Houston Calculated using data from the American Community Survey, National Household Travel Survey, EIA, ElectricityLocal, and Zillow 16

18 Limitations Homogeneous agents Single transportation mode (driving) Monocentric urban form Does not consider dynamics No traffic congestion Linear relationship for CO 2 emissions 17

19 Central City FAR Restriction 18

20 Central City FAR Restriction 19

21 Suburban FAR Restriction 20

22 Suburban FAR Restriction 21

23 UGB 22

24 UGB 23

25 Policy Implications FAR restrictions increase emissions by causing a city to expand spatially, and even more so if they induce migration to more emissions-intensive urban areas UGBs likely reduce overall emissions even though inter-city migration can diminish the effect - Additional calculations show that the CO 2 abatement cost associated with a UGB is very high - Climate mitigation benefits alone do not appear to justify the harm it does to consumers through higher housing prices 24

26 Policy Implications Imposing a UGB in an emissions-intensive urban area could be a powerful emissions reduction tool, because the inter-city migration effect would work in the same direction as intra-city densification Housing prices should not be ignored in analyses of land-use regulations - They have a significant impact on consumer utility and urban form 25

27 Incorporating Green Buildings Energy efficiency of housing could adjust endogenously within the model - Function of building type (population density) - Consumer optimization of efficiency investment Examine the effects of efficiency standards and their interaction with land-use regulations - Might also have an important effect on housing prices Like UGBs, green buildings would have the greatest impact in the most emissions-intensive urban areas 26

28 The end Thank you for attending! Some additions to the Austin skyline,