2014 Progress Report: Characterization Of Emissions From Small, Variable Solid Fuel Combustion Sources For Determining Global Emissions And Climate ImpactEPA Grant Number: R835036
Title: Characterization Of Emissions From Small, Variable Solid Fuel Combustion Sources For Determining Global Emissions And Climate Impact
Investigators: Edwards, Rufus D. , Bond, Tami C. , Smith, Kirk R.
Institution: University of California - Irvine
EPA Project Officer: Hunt, Sherri
Project Period: September 1, 2011 through August 31, 2014 (Extended to August 31, 2016)
Project Period Covered by this Report: September 1, 2013 through August 31,2014
Project Amount: $900,000
RFA: Black Carbon's Role In Global To Local Scale Climate And Air Quality (2010) RFA Text | Recipients Lists
Research Category: Global Climate Change , Climate Change , Air
Obtain climate-relevant data from in field measurements of household stoves and rural small-scale industries, using a combination of real-time measurements, chemical characterization, and statistical analysis.
In the previous 2 years, 242 home measurements and 24 small-scale industry measurements were made (see table below). In addition, we have analyzed EC/OC on previously collected quartz filters from El Salvador to evaluate the potential impact of forced draft advanced combustion stoves on mitigation of BC emissions. Because data analysis and data quality checking are still ongoing, the final sample numbers will be reflected in the forthcoming papers. The intensive field measurement and sample analysis schedule means we have substantial analysis of the data and writing up of results that are necessary on the samples that have been collected.
During the current reporting period, lab analysis of OC/EC data for all field campaigns was completed. A comparative analysis of emission factors was completed, considering fuels and stoves measured under this grant as well as previous field samples. The results were compared to lab tests of similar stoves to show that most lab tests underestimate PM emissions. This work creates a better understanding of the traditional stove emission factors globally, as well as factors that influence emissions. Fuel type, for example, was found to influence emission factors in the same type of stove in Nepal. Most of the PM emissions from Yunnan stoves occur during the start-up period when a mixture of coal and biomass is ignited in a cold stove. Thus, emissions factors are highly dependent on when the measurements are taken in the burn cycle. There were regional differences as well; Tibet and Indian stoves were high particulate matter emitters, especially non-chimney stoves burning dung. Yunnan emissions are roughly comparable to Honduras and Nepal, but Tibet and Indian dung stoves are much higher.
Analysis also was completed on a pilot study of non-household stove emissions. These measurements represent the first known samples collected from some untested, but common village-level combustion sources. Winter heating with straw in the Nepal plains, for example, produces very high CO and PM emission factors, and is a source that is not included in current emission inventories.
On consultation with EPA, we deferred the site visit to El Salvador as the economic downturn caused a collapse in carbon markets that largely delayed the dissemination of these household stoves in a wider population. Because we previously measured 23 stoves that are in houses, and also a representative sample of 25 stoves from schools, the merits of measuring the same stoves again were limited in comparison to the costs. We have analyzed EC/OC on quartz filters that were previously collected in a sub sample of schools and houses in El Salvador to evaluate the potential impact of forced draft advanced combustion stoves on mitigation of BC emissions as part of the current project. Results show that significant climate benefits can be achieved with advanced combustion stoves, which could substantially defer the cost of stove technologies, with benefits up to 78 USD per stove per year using a social cost of 47 USD per tonne CO2 equivalent.
Building off lessons learned during the 2013 Yunnan field campaign, a new iteration of the PSAP portable sampling system was developed in 2014 incorporating many improvements to make the equipment easier to use and less intrusive to the household while increasing the quality of data and providing more robust and dependable data collection. The layout of the sensor box was redesigned so the equipment can be operated with the lid closed to protect from sun, rain, and dust and allow for quicker setup time at the household. The run time was doubled by reducing the power consumption and making space for more batteries. Additional flow meters were added to allow real-time measurement of the dilution ratio for quality control and sampling adjustments on the fly. Major improvements were made to the data acquisition system including an on-board SD card data logger, new open-source firmware that is more configurable and versatile, new open-source computer software for simple real-time data monitoring, and a wireless transmitter for remote data monitoring. These changes ensure dependable data collection and create a user-friendly front end for operating the sampling system.
Planned activities for the upcoming year include analysis of the data that have been collected and writing up of results, including a review of priorities for further field measurements.