6 Replies Latest reply: Jul 17, 2014 11:03 AM by crispin RSS

    The only way UB can reach exposure levels compatible with international norms is to substitute clean fuels for household coal use over the next 10 years?

    665682 C4D Master

      Since we have a stove switch program in Mongolia going on, hope to see some discussions on the recent conclusion of the paper. Below is the description from the author and the link of the paper.

      http://ehs.sph.berkeley.edu/krsmith/publications/2014/UB%20Final%20Report%20-%20June%209.pdf

       

      Below is the short executive summary of a report we just finished for the Gov of

      Mongolia (full report on the website below).  Ulaanbaatar (UB) has some of the

      worst urban winter air pollution in the world driven by topography, (narrow

      valleys), meteorology (wintertime inversions), climate (coldest capital city in

      the world), population (rapid rural-urban migration retaining rural housing and

      heating modes), and fuel choice (mostly coal, particularly for household

      heating).  We estimate the health impacts of the current air pollution situation

      and three future scenarios with increasing amounts of control measures for both

      household and other sources of pollution.

       

      We believe that this study is pioneering in several respects, as described in more detail in the report. 

      Among these is that its primary metric is total exposure, not indoor, not

      outdoor, but integrated exposure considering where the different population

      groups spend time.  It thus includes both the contribution of outdoor pollution

      to indoor levels through penetration into the households, but also the

      contribution of household coal burning to outdoor levels.  We are not aware of

      any other study that has done this in the context of interventions in a real

      city using local data.  (but please let me know if there is one)  It is also one

      of the first to apply the new Integrated Exposure-Response curves developed for

      the GBD exercise in a forward-looking assessment.

       

      We conclude that the only way UB can reach exposure levels compatible with international norms is to

      substitute clean fuels for household coal use over the next 10 years.   We do

      not go into detail, but there are options for this outside of importing fuels

      including synthetic LPG (DME) now being planned for production from synfuel

      plants in Mongolia.  Accelerating the trends toward various district heating

      arrangements can also help.

       

      We point out that unlike many other polluted cities (Beijing and Delhi, for example), UB does not receive any significant

      pollution from nearby areas, being in the middle of the least densely populated

      country in the world.  Thus, unlike those other cities, UB holds its air pollution fate essentially entirely in its own hands. 

        • Re: The only way UB can reach exposure levels compatible with international norms is to substitute clean fuels for household coal use over the next 10 years?
          C4D Explorer

          Dear Yabei,

          Mongolia, as you know, is a big producer of methanol. Methanol is an ideal cooking fuel and is very cheap, much cheaper than DME or LPG. It also has the advantage of being a liquid fuel rather than a gaseous fuel.  So it is more easily handled.

           

          We have developed a safe way to handle methanol in a supply chain for very safe and efficient cookstoves, where it is not handled as a free liquid, but rather, adsorbed into a fuel canister.  We are doing this work in locations where there is an abundance of natural gas available, especially natural gas that does not have a market and as a consequence is flared.

           

          If you would like to learn about what we are doing, please visit our website at www.projectgaia.com or email us at info@projectgaia.com.

           

          Methanol can be blended with ethanol to make an excellent cooking fuel, or it can be used without blending with ethanol. Both simple alcohols, ethanol and methanol, make ideal, very clean-burning cooking fuels when used in a properly designed stove. But, as with any other fuel, we urge that these fuels be used only with a properly designed stove and with a safe handling procedure,

            • Re: The only way UB can reach exposure levels compatible with international norms is to substitute clean fuels for household coal use over the next 10 years?
              665682 C4D Master

              Harry,

               

              Thanks for the interesting information you provided. It will be good to know the economics of promoting methanol for cooking and how it compares to other alternatives. Is it possible for heating too as heating demand is much higher? Also, what's the market potential for this technology in Mongolia? I always think that solutions have to fit into the local condtions which include resource availability, development status, people's needs, etc. So an initial maket study would be essential.

              • Re: The only way UB can reach exposure levels compatible with international norms is to substitute clean fuels for household coal use over the next 10 years?
                rvanderplas C4D Enthusiast

                Harry,

                 

                When it is cold, people use 25 kg of coal or more per day; remember, the stoves are mainly for heating, cooking is a nice feature. Coal is available at very low prices. I sincerely doubt that ethanol or methanol can compete with coal. There are 160-180 thousand households using coal at the moment. This scale would be a serious issue for ethanol or methanol production.

                  • Re: The only way UB can reach exposure levels compatible with international norms is to substitute clean fuels for household coal use over the next 10 years?
                    crispin C4D Expert

                    Thanks Robert for pointing that out.

                     

                    It may be helpful to note that in houses 'with a bit of money' people are cooking with a different fuel from the space heating. Because of cost, coal is likely to be the main heating fuel for many years. It is available, cheap and can be burned very cleanly in terms of PM and CO.

                     

                    With cooking however, there is such a long delay between ignition and cooking compared with electricity or gas, there is a move towards using something else for cooking tasks, particularly short ones. This is noticeable in Indonesia where even 'very poor' households use LPG for reheating food or making tea.

                     

                    If the heating and cooking tasks are separated both physically and in terms of fuel (as happens here in Canada with fuel oil and electricity) many possibilities arise that are financially and culturally attractive. Most cooks do not want to clean fire-blackened pots. That means methanol/ethanol is a possible answer. For coal, the long term answer is processed coal in the form of raw coal pellets of a size appropriate for small automated burners. Once lit, such a space heater can even emit less PM2.5 than a cooking stove.

                  • Re: The only way UB can reach exposure levels compatible with international norms is to substitute clean fuels for household coal use over the next 10 years?
                    crispin C4D Expert

                    Hi Harry

                     

                    Indonesia)  The protocols for the baseline are established by actual cooking. Prof Annegarn reported that it was quickly determined that the Heat Flow Rate (HFR) which is the number of Joules entering the pot per square cm of heated surface, was not high enough to meet the minimum cooking power required to prepare the foods people eat. The HFR was 1.6 Watts per sq cm. The inventor had never been challenged to create a particular heat transfer rate. He went home and quickly returned with a rating of 2.0 which is just enough to meet the demand.

                     

                    I suggest that this is a culturally relevant metric that serves as a minimum performance guide. In the CSI-Indonesia Pilot programme the required target is >3.0 w/cm^2 for Central Java. Using this as a guide, you will be able to test your methanol and ethanol stoves to see if they are going to find acceptance on that score.

                     

                    Other metrics include the turn down ratio (again provided by the HFR, not just a ratio), durability, cost, required attention time, fuel flexibility, speed of ignition and pride of ownership. Some have numbers, some are evaluations of opinion. It appears a new standard is about to emerge.

                  • Re: The only way UB can reach exposure levels compatible with international norms is to substitute clean fuels for household coal use over the next 10 years?
                    crispin C4D Expert

                    There are some recent developments that speak to the general claims in the paper above. The recently released report by Professor Lodoysamba from the National University of Mongolia provides some relevant perspective and PM measurement data.

                     

                    I have provided a link to the report on my site:

                    http://www.newdawnengineering.com/website/library/Papers+Articles/Mongolia/Air%20Quality%20in%20UB%20Lodoysamba_2014.pdf

                     

                    There are some PM10 measuring stations in Ulaanbaatar but they do not collect PM2.5 measurements simultaneously. Some data from GIZ stations exists from a few years ago which provides neighbourhood comparisons but it is getting stale.  Only one station has long term PM2.5, and a significant problem is that the data for both (PM 10 and 2.5) are needed in order to perform policy analysis.

                     

                    The KRSmith paper it is based on a year of measurements in Ulaanbaatar but unfortunately 1 year is not enough information to make a projection based on measurements alone because there is no trend. This explains why they have (quite reasonably) used a model for predicting future PM concentrations. This points to the urgent need to establish additional PM10 and PM2.5 stations. International standards call for one station per 150,000 population which means about 6 or 7 permanent stations for Ulaanbaatar.

                     

                    In the Lodoysamba presentation some valuable measurement data is reported showing for perhaps the first time the trends in PM2.5 and to a certain extent, an indication of PM2.5 relative to PM10. PM2.5 mass is included in PM10. [The numbers mean 'smaller than 2.5 microns' and 'smaller than 10 microns' which includes the 2.5 micron fraction.]

                     

                    The most relevant point is that during the implementation of the stove replacement programme over the past 2.5 years the PM2.5 level, which accounts for nearly all the domestic stove emissions, has dropped by just over 20% per year. That is, the PM2.5 level has been reduced by more than 40% in only 2 years. Ger stoves do not make large particles.  This drop coincides with two things: the rollout of the improved stove programme, and the gradual switch from Baganuur coal to coal from the Nalaikh mine east of the city. This combination has led to this dramatic improvement in the city air in spite of the significant increase in the number of people in the city and the increase in the number of vehicles.

                     

                    Because of sparse data, it is not possible to make reasonable projections of future emissions with confidence, however it is possible to make two statements about the scenarios in the KRSmith paper. The first is called the 'current situation' or perhaps the 'do nothing' scenario. This models a slow rise in the annual average from 72 microgrammes per cubic metre following an expected population increase. The next is Scenario One which assumes the invention of a future technology clean-burning coal stove that will reduce the remaining emissions by 60% from the present 90% reduction currently allowed for participating stoves in the replacement programme. In other words, the current performance target is a 90% reduction compared with the baseline traditional stove. A reduction of another 60% of the remainder (for a total of 96% reduction) would, according to the model, reduce PM to 40 or so microgrammes per cubic metre (annual average exposure). Scenario Two proposes the achievement of the current WHO target of 11 microgrammes by the complete banning of all solid fuel combustion in the city and replacing it with liquid fuel alternatives and [coal-fired] electricity.

                     

                    From the data presented by Lodoysamba, one is able to make to comments that will stand on measurements alone.  They are that scenario One is already being achieved in that a) the stoves passing the test are on average more than 96% cleaner than the baseline (even though the target is 90%) and b) the PM2.5 level is dropping at 20% per year, faster than anticipated by Scenario One. The second is that the contribution to total PM2.5 from domestic stoves is probably less than 50% (47% with another unallocated 10% from all sources). This means that even if all solid fuel burning ceased tomorrow, the PM2.5 level would not drop to anything close to the WHO limit because it is not as big a portion as is generally assumed.

                     

                    The implications of point two are significant. If domestic stoves are already less than 50% of PM2.5, and are dropping fast even as the total drops relative to PM10, then there is not much the City needs to do other than to carry on with the stove replacement programme.  It is having the desired effect and the cost is far less than the benefit.

                     

                    There is a further contribution from Prof Lodoysamba which is that the calculation of an annual average exposure is, or can be, quite misleading about the wintertime exposure. For that reason he proposes that as there is very little PM2.5 in summer, the period for analysis should be 1 October to 31 March. It is during this time that the air is poor.  Examining this period, he plots the exposure levels (what is known) for PM10 and PM2.5 showing how it evolves during the day, the weekends, and the winter. Using source apportionment methods refined over the past decade, he reports the fraction of PM2.5 that originates from 'low temperature coal combustion'. In those Ger areas where stove replacement has been emphasized, the shift is dramatic. The total PM2.5 is well down, and the fraction from stoves is dropping slightly faster.

                     

                    What this points to is the effectiveness of modern, improved coal stoves. Once the stove development centre that is part of UB Clean Air Project (UB-CAP) is established later this year, the performance of the stoves is expected to improve even further and the threshold proposed by Smith et al Scenario One can be exceeded.  That will, however, not bring the city air in winter below 40-50 microgrammes because it is not a large enough source to do that even if removed entirely.

                     

                    In addition to the Ger stoves, there are more than 20,000 small low pressure boilers (LPB) in the city each of which produces the emissions equal to about 4 Ger stoves. That means some 50% of all PM currently coming from low temperature coal combustion is actually not from Ger stoves but LPB's. Once those units are improved and replaced, there will be a second wave of air quality improvement. This will leave vehicles, dirt roads, fugitive dust and construction as the major contributors to PM each requiring their own solutions.