Consultation on the Low Emission Strategy for Scotland
Responses to this consultation paper are invited. They should be sent along with the completed Respondent Information Form to email@example.com by 10 April 2015
Strategy document [PDF, 1353.2 kb: 16 Jan 2015] & Respondent Information Form and Consultation Questionnaire [DOC, 168.4 kb: 16 Jan 2015]
Information needed to develop an effective low-emissions strategy for Scotland:
1) Air Quality (PM2.5 particulate air pollution) and Mortality in Scotland. A Briefing Paper
2) PM2.5 in Scotland: A Report for SEPA, July 2012
3) Low Emissions Strategy for Scotland
Below are some important issues and information, relating to the questions on the consultation form.
Q1 Do you think the Mission, Vision and Objectives for the Low Emission Strategy are appropriate? If not, what changes would you suggest?
Yes, the Mission, Vision and Objectives for the Low Emission Strategy are appropriate.
Q2 Do you think the proposed actions will deliver the Mission, Vision and Objectives? If not, what changes to the actions would you suggest? Are additional actions required? If so, please suggest what these might be.
No. The Strategy is based on the false assumption that cars are the major source of air pollution. In fact, almost identical amounts of PM2.5 are emitted by residences in Scotland and vehicles (each produce 23.8% of the total). However, vehicle emissions are declining rapidly as Euro-5 and Euro-6 vehicles replace older models. In contrast, residential emissions could skyrocket due to the trend of installing domestic wood-burning stoves, each of which emits more PM2.5 year than 1,000 to 2,000 cars.
A strategy focussing on vehicle emissions (which are declining anyway) but ignoring the trend to install devices at least 1,000 times more polluting than the average petrol car, is not the best way to protect health or the environment.
Dangers of increased pollution from increasing use of wood stoves now being recognized.
“Even modest domestic wood-burning may lead to particulate exposures comparable to those from traffic sources. We need to manage urban emissions to ensure that increased wood-burning does not offset schemes to reduce traffic pollution.” http://www.birminghammail.co.uk/news/health/wood-burning-stoves-in-pollution-shock-8378404
The quote is from an article in the Birmingham Mail. It explains that a domestic wood stove is as bad as an old diesel car. In fact, it’s probably much worse. Measured real-life PM2.5 emissions from stoves that meet the current USEPA standard are about 2,200 times worse than a petrol car - woodsmoke.3sc.net/woodheater-car-comparison#USEPA There's no reason to believe that DEFRA-approved stoves for use in smokeless zones are any better.
The proposed policy encourages cycling to reduce pollution. Although cycling 1,000 km per year instead of driving might seem like a considerable effort, it will avoid just 1 gram of PM2.5 emissions, compared to driving the same distance in a petrol car, or just 5 grams for an Euro-5 compliant diesel.
A feature story in the Aberdeen Press and Journal shows that wood burning stoves are becoming increasingly popular in Scotland, with the increased PM2.5 emissions likely to be many times greater than any reductions in traffic emissions www.pressandjournal.co.uk/fp/lifestyle/home/478840/top-five-tips-wood-burning-stoves
Typical real-life emissions from domestic wood-burning stoves are about 10 grams PM2.5 per hour - using one for just 6 minutes will completely counteract the benefits of cycling 1,000 km instead of driving a petrol car. Using one for 30 minutes will completely counteract the benefits of cycling 1,000 km instead of driving the distance in a Euro-5 diesel car.
To prevent the reductions in vehicle pollution being offset by increased PM2.5 pollution from domestic wood stoves, low emissions zones should not permit new wood stoves to be installed unless their average annual PM2.5 emissions are no greater than those of the average vehicle that will be permitted to use the zones.
The UN Environment Program and World Meteorological Association recommend phasing out log-burning stoves in developed countries to improve health and also reduce global warming from methane, black carbon emissions and other short-lived climate altering pollutants (CAP). There is very little public awareness that, even if CO2 emissions from are ignored, the emission of other CAP from current wood stove models actually cause more global warming than other forms of heating - woodsmoke.3sc.net/ghgResidential PM2.5 emissions already as high as those from traffic - could easily double if 1 household in 100 uses a wood stove
Road transport emits 1.67 kilotonnes of PM2.5 per year (23.8% of PM2.5 emissions), almost identical to the 1.63 kilotonnes (23.8% of PM2.5 emissions) from residential sources - see ‘PM2.5 in Scotland: A Report for SEPA’, published in July 2012 by Air Quality Consultants.
This report comments on the discrepancy between NOx and PM2.5: “ nitrogen oxides concentrations at Glasgow Kerbside fall during the day (Figure 12), from a morning rush-hour peak (peaking at 08:00-09:00h), whereas the PM2.5 concentrations remain steady throughout the daytime (Figure 11). It is known that the numbers of heavy duty vehicles on the road, and hence exhaust emissions of nitrogen oxides, decrease during the day from a morning peak (Beevers et al., 2009)…. It is thus evident from the analysis of the data for the two sites in Glasgow that while road traffic is likely to be an important source of PM2.5, vehicle exhausts are not the only contributor” …
Page 28 of this report states: “Indeed, one wood burning source in 250 properties, the rest using gas, would generate a (PM2.5:NOx) ratio of 0.054”. Solid fuel burning is the major source of residential PM2.5 emissions. If (as seems likely) one household in 250 using a wood stove creates emissions approaching 1.63 kilotonnes of PM2.5 from residential ares, current trends of increasing popularity of wood stoves might lead to 1 household in 100 using a wood stove, leading to a doubling of PM2.5 pollution from residential areas, representing an increase in overall pollution even if every single vehicle was removed from Scotland’s roads!
Consumers (and legislators) need better information on health costs
Consumers and legislators need better information about the health costs of the air pollution from different sources. For example, the health costs of 1 kg of PM2.5 emissions are estimated at about £100, increasing to over £200 for large urban areas with more than a million inhabitants. New wood stoves emit 20 to 40 kg of PM2.5 per year, leading to estimated health costs of £2,000 to £4,000 per year.
Why not develop an air pollution index that relates directly to health effects?
Consumers also need better information about how air pollution indices relate to health. For example, Scotland’s average anthropogenic PM2.5 of 6.8 ug/m3 is estimated to cause 2094 premature deaths per year (5.7 per day), equivalent to the loss of 22,474 years of life (62 life years lost per day). How does this relate to the air quality index? It would be more useful if the index rated days according to how many people are expected to die prematurely at that level of continuous exposure, e.g. less than 3 deaths per day might quality as “good”, less than the average of 5.7 deaths per day as tolerable, and anything over the 6 premature deaths per day as undesirable.
The current air quality index is extremely difficult to understand and may not adequately convey the health information. For example, a Canadian study reported significant, harmful effects on blood vessel health in healthy volunteers who did not have HEPA filters in their home when outdoor PM2.5 levels, mainly from wood smoke, averaged 10 ug/m3 for 1 week. As far as I can tell, the Scottish AQI would record a week of PM2.5 levels of 10 ug/m3 as ‘good’. Yet clearly this isn't the case. The AQI should therefore be changed so that PM2.5 above 10 ug/m3 are described as moderate air pollution, or better still, an alternative AQI that indicates the number of premature deaths or other health effects should be developed.
Q3 Does the Setting the Scene section accurately summarise the current policy situation? Please suggest changes if not.
Section 5.6 of the Strategy document states: “The Scottish Government has declared a preferred policy of biomass being deployed in heat-only or combined heat and power schemes and off the gas grid. In areas where AQMAs have been declared, the expectation is that biomass deployment will focus on larger, more efficient plant incorporating advanced filtration technology to minimise emissions.”
The above strategy does not reflect the reality of increasing numbers of wood-burning stoves being installed
Although this strategy seems OK, it does not accord with the reality of increasing popularity of domestic wood-burning stoves. Current standards for household stoves, even those permitted in smokeless zones, do not prevent excessive emissions. Virtually all of London is a smokeless zone, yet “Aethalometer wood burning tracers suggests that the annual mean concentration of PM10 from wood burning was 1.1 ug/m3. To put this in a policy context, this PM10 from wood burning is considerably greater than the citywide mean PM10 reduction of 0.17 ug/m3 predicted from the first two phases of the London Low Emission Zone which was introduced to reduce PM from traffic sources.” http://www.sciencedirect.com/science/article/pii/S1352231013009825
Similar concerns were expressed in the UK Guardian:
“East Sussex Fire Service issued public warnings following a spate of chimney fires on Boxing Day, a symptom of the increasing popularity of open fires and wood stoves as secondary or decorative heating….
“Between Christmas and New Year traffic pollution declined in the early evening, but airborne particles continued to increase until just before midnight, indicative of smoke from household fires. This was especially apparent across the south in Bristol, Eastbourne, Oxford and Reading and also in Cardiff, Southampton and parts of London. In Eastbourne particle concentrations quadrupled each evening; in Bristol they increased by more than five times.
“Domestic wood burning takes place where people live, at the times when everyone else is at home. Even modest wood burning in densely populated areas can lead to harmful pollution exposures comparable to those from traffic. Home wood burning needs to be addressed before more people invest in stoves or make open fires a feature in their living rooms.
“In Paris wood burning has become entrenched and recent proposals for a ban met fierce resistance, despite evidence that home wood burning is causing one third of the city’s emissions of airborne particle pollution.”http://www.theguardian.com/environment/2015/jan/11/pollutionwatch-dont-keep-fires-burning
The large increases cited above – 4-fold increases in Eastbourne, 5-fold increases in Bristol demonstrate the magnitude of the problem in Scotland if nothing is done.
The trend towards home wood burning happening in Scotland - www.pressandjournal.co.uk/fp/lifestyle/home/478840/top-five-tips-wood-burning-stoves
A peer-reviewed paper published in Australia noted that “With average firewood consumption of about 2 tonnes/year, the average brand new wood-heater emits about 20 kg PM2.5 and has estimated health costs (using the NEPC economic analysis estimate of $280/kg for PM.5 emissions in Sydney) of $5,600 per year …. the average new wood-heater emits more PM2.5 pollution per year than 1,000 passenger cars, that woodsmoke caused 16 (softwood) to 3 (hardwood) times more tumours in tests on mice than the same amount of cigarette smoke and that a typical evening burning 15 kg of wood puts out as much PM2.5 as in the smoke of 7,500 cigarettes.”
“Residential wood-heater emissions peak in July at 1.4 thousand tonnes, compared to about 0.45 thousand tonnes for all other sources. This is despite the fact that only 4.3% of households in Sydney used wood as the main form of heating in 2008 (ABS 2008). For the whole year, the (emissions) inventory lists 5,457 tonnes of PM2.5 from Sydney’s wood-heaters (50.6% of man-made PM2.5 emissions), compared to 1,553 tonnes from on-road vehicles, 1,935 from industry, 952 from off-road vehicles and 881 tonnes from other sources (NSWEPA 2013).”
One wood stove emits more PM2.5 pollution per year than 1,000 cars
Although it is easy to find lists of DEFRA-approved stoves for smokeless zones, there is no accompanying information on how stoves are tested or expected real-life emissions. Studies elsewhere show that real-life emissions bear little relationship to measurements from a perfectly-operated wood stove in laboratory conditions. Consequently, emissions from a new log-burning stove permitted in UK smokeless zones are likely to be similar to those from wood stoves satisfying the appropriate Australian/New Zealand standard (AS/NZS 4013), USEPA-certified stoves, or those permitted in Denmark, where 64-70% of all PM2.5 emissions originate from wood stoves. A Norwegian study reported that the estimated health costs of wood stoves were very high – 10,000-14,000 kr (US$1,193-1,671) per year per stove, for references see http://woodsmoke.3sc.net/denmark .
To avoid this problem, low emissions zones should also require low-emissions stoves. Emissions from a petrol car average about 1 mg/km (see woodsmoke.3sc.net/woodheater-car-comparison#USEPA . The Euro-5 limit for diesel cars is 5 mg/km. Hence PM2.5 exhaust emissions from a petrol or diesel car travelling 20,000 km in a low emission zone should range from about 20 to 100 grams per year. Similar requirements should apply to any domestic stove installed in a low emission zone. In Scotland, heating can be required for perhaps 10 hours per day, 200 days per year, i.e. 2,000 hours per year. To ensure that a domestic stove is no more polluting than an Euro-5 diesel, PM2.5 emissions should be less than 50 mg/hour or 5 mg per kg wood burned.
Recommended change - Low emission zones need low emission wood stoves
Setting a strict standard is likely to stimulate the required research and development into clean-burning stoves that will make it possible to use wood-burning stoves in low emission zones, just as setting the strict PM2.5 limits for diesel cars allowed them to become much cleaner. In 1989, the average diesel car in emitted 0.75 grams PM2.5 per km, as discussed on page 3 of the peer-reviewed research paper: Air pollution in Australia: review of costs, sources and potential solutions. The current standard for diesel cars represents a reduction of more than 99%.
Over the same period, real-life emissions from the average wood stove have improved only marginally. In 2013, seven US states sued the USEPA because of their ""25 years of inaction on woodstove emission standards violates the Clean Air Act". The resultant action could unfortunately be described as “too little, too late”. New standards of 4.5 g/hr (for both catalytic and non- catalytic models) will apply to stoves sold in the US in 2016, with a stricter standard of 2.0 g/hr in 2020.
However, the USEPA certification process measures emissions from a correctly-operated stove burning ‘cribs’ (lumber assembled in a standardized configuration based on the type of heater being tested). The USEPA believes the development of wood heaters that perform well in cordwood testing is important, because cordwood is what consumers use. A slightly higher limit of 2.5 g/hr will apply to tests using seasoned cordwood, but EPA approval of the test method will be required before a new test will be considered valid.
Real-life emissions of 16 stoves in Klamath Falls and Portland, Oregon were compared with their EPA-certification values in a report published in 2000. The
EPA-certification values of the non-catalytic stoves averaged 4.2 grams/hour, much lower than average real-life emissions of 9.7 grams/hr. EPA-certification values of catalytic stoves averaged 3.5 grams/hour, much lower than average real-life emissions of 13.8 grams/hr.
Yet, as noted above, to ensure that a domestic stove is no more polluting than an Euro-5 diesel, PM2.5 emissions should be less than 50 mg/hour or 5 mg per kg wood burned. To make it no more polluting than a petrol car, it would have to emit less than 10 mg/hr or 1 mg per kg wood burned.
Strict standards are required because there is no safe level of PM2.5 pollution.
Q4 Does the Way Forward section give a reasonable outline of what further action is needed to deliver an effective Low Emission Strategy? Please suggest changes if not.
6.2 Health Tomorrow
“ACTION: Assess case for adopting World Health Organisation guideline values for PM10 and PM2.5 as Scottish objectives”
This would be better phrased as “determine if there are any significant barriers to adopting the WHO PM2.5 and PM10 guidelines”. There is no safe level of PM2.5 pollution, so these guidelines are absolute minimum that needs to be achieved. Any major barriers to meeting these guidelines should be considered and addressed, unless the costs are significantly greater than the estimated health benefits.
Recommendation: re-phrase as: "Adopt the WHO guidelines for PM2.5 and PM2.5" unless there is a compelling case for not doing so.
6.4 Development Tomorrow
Compared to the extensive discussion from p23 to p29 on reducing emissions from transport, there are few plans for reducing residential emissions. This is despite the fact that residential emissions (23.8% of total PM2.5 emissions) are almost identical to the 23.8% of PM2.5 from transport. The case for addressing residential emissions becomes even stronger because of the fact that transport emissions will fall even in the absence of any formal strategy, as older diesels are scrapped and replaced with Euro-5 and Euro-6 compliant vehicles.
In contrast, if nothing is done to address the trend of increasing use of wood for heating, residential PM2.5 emissions could double or even triple. As noted above: “only 4.3% of households in Sydney used wood as the main form of heating in 2008 (ABS 2008). For the whole year, the (emissions) inventory lists 5,457 tonnes of PM2.5 from Sydney’s wood-heaters (50.6% of man-made PM2.5 emissions), compared to 1,553 tonnes from on-road vehicles, 1,935 from industry, 952 from off-road vehicles and 881 tonnes from other sources (NSWEPA 2013).”
Information in ‘PM2.5 in Scotland: A Report for SEPA’ , published in July 2012 by Air Quality Consultants’ suggests that one household in 250 using a wood stove is the major source of the 1.63 kilotonnes of residential PM2.5 emissions in Scotland. If, because of the increasing popularity of domestic wood stoves, this increases to 1 household in 100 using a wood stove, PM2.5 pollution could easily more than double to 4.07 kilotonnes of PM2.5 pollution from residential areas. This would represent an increase in overall pollution even if every single vehicle was removed from Scotland’s roads!
Despite the major threat this poses to air quality and health, there appears to be virtually no recognition or discussion of this major threat. Planning residential areas to improve walking and cycling is desirable because it will allow people to enjoy the health benefit of regular exercise, but with 1 new wood stove expected to emit more PM2.5 pollution in 6 minutes than saved by cycling 1,000 km instead of driving 1,000 km in a petrol car, air quality management should focus on major sources of residential emissions.
More importantly, since 1 household using a wood stove out of every 100 households could have a major impact on pollution, this problem is likely to affect any and all urban areas.
Recommendation: The best approach is therefore a national strategy, e.g. not allowing any new wood stove in any urban area unless its annual PM2.5 emissions are no worse than the average passenger car.
6.5 Climate Change Tomorrow
Recommendation: This section should mention the recommendations of UN Environment Program/World Meteorological Association to phase out open burning of agricultural waste and log-burning wood stoves in developed countries to reduce global warming as well as improve health.
6.8 Behaviour and Communications Tomorrow
Consumers need better information about how air pollution indices relate to health. For example, Scotland’s average anthropogenic PM2.5 of 6.8 ug/m3 is estimated to cause 2094 premature deaths per year (5.7 per day), equivalent to the loss of 22,474 years of life (62 life years lost per day). How is this information conveyed in the air quality index? It would be better to adopt an index that rated days according to how many people are expected to die prematurely at that level of continuous exposure, e.g. less than 3 deaths per day might quality as “good”, less than the average of 5.7 deaths per day as tolerable, and anything over the 6 premature deaths per day as undesirable?
The current air quality index is extremely difficult to understand and may not adequate to convey the health information. For example, a Canadian study reported significant, harmful effects on blood vessel health in healthy volunteers who did not have HEPA filters in their home when outdoor PM2.5 levels, mainly from wood smoke, averaged 10 ug/m3 for 1 week. As far as I can tell, the Scottish AQI would record a week of PM2.5 levels of 10 ug/m3 as ‘good’. Yet clearly this isn’t the case. The AQI should therefore be changed so that days with more than the average of 5.7 PM2.5-related deaths are rated as poor or marginal and that PM2.5 above 10 ug/m3, noted result in damage to the blood vessels of health volunteers who don’t live in houses with HEPA filters, are described as poor or marginal.
1) The AQI should be improved so that it related directly to health, and that by clicking on the score, people can obtain the estimated number of premature deaths, life years lost lost, increased numbers of hospital admissions or restricted activity days.
2) As well as reporting the air quality, people should be given advice about how to reduce emissions, e.g. don’t use wood stoves or older diesels or marginal days and use electric lawnmowers in preference to petrol ones.
Q5 What are your views on the proposals for the National Modelling Framework?
The modelling should aim to estimate population exposure and the health costs of air pollution, so that the most cost-effective ways to reduce the health costs of air pollution can be determined and implemented.
Q6 What are your views on the proposals for the National Low Emission Zone Framework?
It seems a very complicated and expensive way to proceed. Far better to develop a National approach, e.g. gradually increasing taxes on polluting activities (in proportion to the magnitude and health costs of the pollution) so that people gradually convert to cleaner activities, e.g. Euro-5 or Euro-6 diesels, low-emission biomass burners with filtration systems instead of the sort of wood stoves than are becoming trendy and currently being installed in ever-increasing numbers.
Q7 What are your views on the proposed Key Performance Indicators? Are any different or additional Indicators required?
The key performance indicators should be the number of premature deaths related to air pollution, the number of life-years lost, numbers of days spent in hospital and numbers of restricted activity days because of air pollution, or better still the estimated economic cost of the lost life years, days spent in hospital and restricted activity days from air pollution exposure.