Energy and Environment Project 2012-2013: Stove Subsidies Component (Mongolia)

Abstract

This impact evaluation assessed stove performance and impacts under real-world usage conditions. It was designed to answer the following questions:

Evaluation question 1: How do energy-efficient products impact ambient air pollution levels, and health and income of residents in Ulaanbaatar? Specifically:
a) How does the use of MCA stoves affect fuel usage and expenditures?
b) Does the use of MCA stoves affect available household income?
c) What is the impact of MCA stoves on emissions of CO and PM2.5?
d) What is the impact of MCA stoves on indoor concentrations of CO and PM2.5?
e) What would be the estimated change in health for Ulaanbaatar residents?
f) How do MCA stoves affect household expenditures related to respiratory health problems?

Evaluation question 2: How do different MCA stove models and different patterns of usage affect the level of impact on ambient air pollution, and the health and income of households with MCA stoves? Specifically:
a) Do different MCA stove model types impact fuel expenditures, income, and PM2.5 emissions, under typical usage behavior?
b) Do deviations from expected MCA stove usage patterns impact air pollution, health, and income of households with MCA stoves?
c) Did the MCA stove program result in differential impacts on men and women?
d) Does possession of additional energy efficiency products such as vestibules or additional ger insulation modify the impact of MCA stoves on ambient air pollution, health, and income?

Since this program was a market-based intervention, households chose whether to purchase an MCA stove. Because a randomized intervention assignment was not possible and the evaluation was implemented after the project had started, a quasi-experimental propensity score matching (PSM) design was used to adjust for differences between those who did and did not choose to purchase an MCA stove. Matching on propensity scores enabled construction of treatment and comparison groups that were balanced along the observed characteristics, thereby providing a counterfactual for the intervention.

Key findings include:

- Participants in the EEP stove subsidy program had 65% lower emissions of PM2.5 and 16% lower CO emissions, both statistically significant, compared to traditional stoves under typical usage conditions.

- The EEP stove subsidy program reduced ambient PM2.5 concentrations over UB attributable to heating stoves by an estimated 30%, with largest reductions in highly polluted areas that were more heavily targeted by the program.

- Factors known to affect coal consumption differed systematically between Ulzii, Khas, and Dul stove users.

- The EEP stove subsidy program achieved high demand for energy-efficient stoves and satisfaction among stove users; however, some stove limitations remained barriers to satisfaction.

- The EEP stove subsidy program did not achieve significant reductions in daily coal consumption under typical usage conditions.

- Very low compliance with MCA stove operation instructions may have contributed to lack of reduced coal consumption.

- Significant reductions in coal use were observed when households used MCA stoves according to instructions.

- Households using MCA stoves enjoyed significantly higher indoor temperatures, suggesting that users may be sacrificing fuel economy for comfort.

- There is no evidence that the EEP stove subsidy program achieved reductions in overall coal expenditures.

- MCA stove owners in gers with better insulation used less coal than traditional stove owners.

- Observed emissions reductions may have contributed to substantially fewer cases of air pollution-related respiratory illness and related costs.