Grantee Research Project Results
2011 Progress Report: Solsource 3-In-1: Providing Clean Energy to the Poorest 2.5 Billion at a Price They Can Afford
EPA Grant Number: SU834746Title: Solsource 3-In-1: Providing Clean Energy to the Poorest 2.5 Billion at a Price They Can Afford
Investigators: Spengler, John D. , Ezzati, Majid , Kulper, Sloan , Ram, Rajeev , Tai, Xiamao , Yang, Xudong , Wilson, David Gordon , Powers, Catlin Ishihara , Qian, Amy , Amatya, Reja , Zhang, Wendi Xiaowen , Jia, Huaze
Current Investigators: Powers, Catlin Ishihara , Spengler, John D. , Frank, Scot G. , Qian, Amy , Amatya, Reja , Zhang, Wendi Xiaowen , Jia, Huaze , Kulper, Sloan , Ram, Rajeev , Tai, Xiamao , Yang, Xudong , Wilson, David Gordon , Ezzati, Majid
Institution: Harvard University , Tsinghua University , Qinghai Normal University , Massachusetts Institute of Technology
Current Institution: Harvard University , Massachusetts Institute of Technology , Tsinghua University , Qinghai Normal University
EPA Project Officer: Page, Angela
Phase: II
Project Period: August 15, 2010 through August 14, 2012 (Extended to August 14, 2013)
Project Period Covered by this Report: August 15, 2010 through August 14,2011
Project Amount: $75,000
RFA: P3 Awards: A National Student Design Competition for Sustainability Focusing on People, Prosperity and the Planet - Phase 2 (2010) Recipients Lists
Research Category: Pollution Prevention/Sustainable Development , P3 Challenge Area - Air Quality , P3 Challenge Area - Chemical Safety , P3 Awards , Sustainable and Healthy Communities
Objective:
The objectives of this research are to develop a novel solar energy intervention and evaluate its ability to reduce indoor air pollution exposures in nomadic households in western China.
Globally, more than 2.5 billion people currently rely on solid fuels (dung, wood, crop residues, and coal) to meet their basic energy needs.1 These people suffer dangerous exposure to harmful pollution from their fires, causing significant impact on their families and the economies of their nations. Within China alone, more than 500,000 people die every year from exposure to pollution from their stoves. 2
In addition, reliance on wood for fuel contributes to desertification; solid fuels are suspected to contribute disproportionately to climate change; and collecting fuel decreases the amount of time that women spend on education and income-generating activities. Finally, buying non-renewable solid fuels such as coal puts an economic burden on families and inconveniences rural people when special trips are required to transport this fuel.
Previous studies indicate that prior energy interventions in rural China failed to reduce indoor particle pollution below the Chinese national standards (Sinton, 2004; Edwards., 2007). This underscores the continued need for new interventions that better meet rural energy needs while also reducing emissions. In addition, it supports the need for thorough evaluation of new interventions to ascertain whether they meet their social and environmental goals prior to widespread implementation.
In this study we work with nomadic communities to develop an energy technology better suited to their needs and to evaluate the impact of that intervention on indoor air pollution (IAP), biomarkers of IAP exposure, and carbon equivalent emissions (CO2eq) under real use conditions in two nomadic communities in Qinghai, China.
Aim 1: Intervention Development
Develop a novel solar energy technology tailored for nomadic communities in western China through co-‐design. The design will provide a platform for solar cooking, heating, and electricity generation.
Aim 2: Evaluate the Impact of the Intervention
Sub-‐Aim 2.1: Indoor Air Pollution
To quantify changes in indoor CO and PM2.5 due to the intervention.
Sub-‐Aim 2.2: Human Exposure Biomarkers
To quantify changes in carboxyhemoglobin (COHb) and blood pressure (bp) in male and female heads of household due to the intervention.
Sub-‐Aim 2.3: Climate Impacts
To analyze the climate impacts of the intervention based on changes in fuel use patterns within the study communities.
Progress Summary:
Intervention Development
Under Phase 2, four performance field-‐tests of the intervention have been conducted in nomadic and agricultural communities in China along with design changes in response to user feedback. During these trials, the solar cooking component of the intervention showed an average power output of 1,120 watts. The electrical generator showed an output of 20 watts. In one day, the generator was able to store enough energy to power a standard cell phone for 7 days.
User’s main comments and our team’s design responses were as follows.
Comment 1: A desire for more control over the power input to their cookware while using the solar cooker. In traditional stoves, people can adjust the temperature by stoking the fire. In standard solar cookers, however, the user has only one temperature option which is dependent on whatever is supplied by the sun.
Response 1: We developed an adjustment system that enables 6 different power settings while using the solar concentrator. The smallest setting has an average output of 750 watts, while the largest setting has an average output of 1120 watts. This enables people to cook over the temperature range of approximately 80 to 400 degrees Celsius throughout the year.
Comment 2: Desire to interact with the pot more ergonomically. In traditional solar cookers and in our initial models, women had difficulty putting heavy pots on the pot stand because the distance they had to reach to set the pot down was equivalent to their entire arm length or more. In addition, women had to stand in front of the concentrator, exposing their eyes to harmful radiation from the sun.
Response 2: Our new design allows women to approach the pot from behind the solar cooker with a reach distance of 0.2 meters, solving both problems.
Comment 3: Desire for a method of aligning the solar cooker with the sun that was easier to perform during winter when people’s hands are cold. Older solar concentrator designs required people to use a wheel attached to a large screw in order to align the system with the sun. This was painful for people during the cold winters as the systems required considerable force and the wheels were typically made from metal.
Response 3: We have developed a lever system for adjustments based on the methods already used to load bags onto pack animals within the target population. In this system, people can align the concentrator standing in one single position, using very little force, and interacting only with nonconductive materials. This minimizes thermal discomfort and maximizes ease of alignment.
Comment 4: Desire for more user-‐friendly packaging of the electric generator to minimize interaction with wiring.
Response 4: Full wire packaging and interfacing of wire casings with the solar concentrator.
Study Population and Approvals
Two nomadic communities have been identified for our randomized controlled trial (RCT) evaluating the solar intervention. One hundred families within these communities have agreed to participate through our informed consent process (under purview of the Harvard Institutional Review Board and the Chinese Science and Technology Bureau). Ten field assistants from within the community have undergone training relevant to their duties in this study: administering surveys and monitoring equipment.
Study Equipment and Supplies
All of the equipment and supplies necessary to achieve Aims 1 and 3 has been purchased and transported to the study location. Half of the equipment and supplies necessary to achieve Aim 2 have ben purchased and transported to the study location. Field assistants have been trained in the operation and maintenance of all equipment already transported to the study location.
Baseline Data Collection
Baseline surveys, fuel data, and particle data have been collected for all households and will be analyzed in January-‐February 2012 at the Harvard-‐EPA particle laboratory. Carbon monoxide (CO), carboxyhemoglobin (COHb), oxygen saturation, and heart rate have been measured for a subset of the population. A second round of baseline data with full measurement in all households will be conducted in
February-‐March 2012.
Preliminary data indicates that indoor concentrations of carbon monoxide from biomass stoves may be harmful to overall health, reproduction, and cognition in study households (Table 1).
Carbon Monoxide Poisoning Level | Sustained CO (ppm) Exposure |
CO in blood (COHb %) | % of Study Families Experiencing This Level | |
Summer | Winter | |||
None | <60 | <10 | 0% | 22% |
Mild | 60-‐159 | 10-‐20 | 67% | 20% |
Medium | 160-‐200 | 21-‐25 | 22% | 33% |
Severe | >200 | >25 | 11% | 0% |
Table 1. Indoor CO and subject COHb observed in study population
Respirable particles (PM2.5) measured gravimetrically in study households have consistently ranged from 1–2 mg/m3.
Future Activities:
>Intervention– Nomadic households in western China prefer clean cooking options that have temperature controls and that can be operated comfortably by people less than 5 feet tall and at temperatures less than -‐15 C. People are uncomfortable using transparent electronics and prefer all wiring to be fully encased.
>Intervention Randomized Controlled Trial-‐ Preliminary results indicate indoor air pollution levels (CO and PM2.5) harmful to human health. Baseline data collection will conclude this winter. The Intervention RCT component of this study will commence in summer 2012 and run through winter of 2013.
References:
Energy and the World. World Bank. 2011
China: Country Profile of Burden of Disease. World Health Organization. 2009
Supplemental Keywords:
solar energy, impact evaluation, intervention study, China energy, China air quality, Qinghai, Tibetan Plateau, cookstoveProgress and Final Reports:
Original AbstractP3 Phase I:
The SolSource 3-in-1: A Comprehensive Decentralized Solar Energy Platform | Final ReportThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.