Ten effective ways to reduce global warming
30 March 2010
There are three main approaches to tacking global warming: through policy measures, economic mechanisms and technological changes. These are obviously interdependent and should be tackled simultaneously.
The two big policy elephant’s in the room are economic growth and population growth which drive consumption and the release of greenhouse gases. Without subduing these, any attempts at mitigating global warming through technological means alone will be completely undermined. We also need to replace the flawed economic mechanisms which have proven largely ineffective due to the lobbying and misuse of credits. The technological solutions themselves should focus initially on the sectors responsible for the greatest net warming over the short term. This will give us a window of opportunity to reduce greenhouse gases from other sectors which will exhibit substantial net warming over the longer term. We now examine these in more detail.
POLICY ISSUES
1. Educate children about how to live a sustainable lifestyle
Our children will be left with the consequences of our unsustainable lifestyles so it is essential they understand the facts about climate change free of the orchestrated misinformation campaigns which have become endemic in the low quality media. This could be introduced as part of a wider subject area in the educational curriculum on how to make rational judgements based on evidence, and how to avoid being influenced by style, advertising and spin.
However, the science is just the easy part. We are also inundated with the pressure to consume, which makes it even more essential to avoid unsustainable thinking habits from an early age. Children should be taught that sustainability is not just about buying more energy efficient products, but also designing to last, making full use of what we have, eating less, wasting less and recycling more. Above all we need to teach that materialistic gain only produces temporary pleasure, and the route to genuine happiness lies in a less competitive, more co-operative society with strong social ties.
2. Control population through family planning, welfare reforms and the empowerment of women
The world's population is expected to increase from 6.8 billion in 2009, to reach 9.15 billion in 2050, with most of this growth taking place in the developing world. Urgent measures are needed to limit global population at levels which can be sustained in the long term, since our culture encourages everyone to strive for the highest material affluence. Unrestrained population growth is a carbon time bomb, which is now only starting to take effect in South East Asia, with South America soon to follow. Unfortunately high fertility rates remain the norm in Sub-Saharan Africa, Pakistan and a number of smaller countries. The only ethical way we can avoid a vast increase in potentially wealthy consumers is by minimising birth rates.
Population growth can be controlled through a combination of measures. These include free and easy access to family planning, welfare provision to encourage smaller families, and the empowerment of women through education and freedom to choose their future. In practice, educated women have less children due to career commitments and the social freedom from the early responsibilities of motherhood.
Contraception is almost five times cheaper than conventional green technologies as a means of combating climate change. Each $7 (£4) spent on basic family planning over the next four decades would reduce global CO2 emissions by more than a tonne. To achieve the same result with low-carbon technologies would cost a minimum of $32 (£19).
Over zealous methods to reduce population could however result in demographic problems with too few children to look after the old, or females in relation to males in future years. Unfortunately population control just like dieting needs to be planned over the long term and no quick fix is possible without introducing other problems.
ECONOMIC MECHANISMS
3. Encourage reforestation and sustainable land use through a combination of economic restrictions and incentives
90% of deforestation is caused by unsustainable agricultural practices, while the logging and plantation forestry play a greater role in forest degradation.
Tropical countries should be paid to reforest net land with natural vegetation, verified via satellite imagery and paid via a carbon tax from industry (see item 4). The price should be set so it is more financially beneficial for countries to reforest and maintain forest habitats than grow crops, biofuels and raise cattle. This system would be far more effective than present financial instruments such as negotiable caps and less susceptible to manipulation since the reforestation would be genuinely additional. Higher latitude countries could be included in this scheme if the combined affect of the carbon absorption and albedo change from forestation reduces net heat gain in these locations.
Further carbon reductions in our biofuel and food chain can be made through changes in our farming practices, such as using crop rotation, no till agriculture, and appropriate fertiliser use. These practices would also reduce pollution in rivers and reduce the degradation of the coastal ecosystems that help to absorb carbon.
4. Introduce a carbon tax and carbon index for businesses*
Corporations are fond of publicising their green credentials, however, these often consist of isolated initiatives with only a limited environmental impact on their business as a whole. It remains the norm for organisations to use energy inefficient offices and send their employees to conferences and meetings that could easily have been accomplished through teleconferencing. Even some businesses which advise on sustainability issues are almost indistinguishable from their clients in this respect. These companies hardly provide a good example!
To avoid this greenwashing all companies should pay a carbon tax. This would be based on the energy used to power, heat and cool their buildings and the fuel used during their employees commuting and business travel. These figures should be calculable from energy and fuel bill receipts, and require only limited additional administrative effort. The monies collected could then be used to fund cost effective carbon mitigation projects such as reforestation, population control and biochar sequestration.
The carbon emitted from each company could also be expressed as a carbon index in terms of the carbon emitted per employee hour and company turnover. This could be prominently displayed on the corporate literature to ensure each company's true commitment and environmental credentials can be judged with respect to other similar organisations, at least in terms of carbon emissions. Government contracts could also ascribe priority to firms who fall within carbon intensity guidelines, although there may be other environmental and ethical issues to be considered in this choice.
However, this system would not take full account of the environmental externalities of the products being purchased for the business; this could be better addressed through taxes on imports from countries that do not apply these criteria, and regulating practices which contribute to waste, such as food pricing and packaging. While this accounting procedure is far from perfect, it is far more important that carbon calculations should be kept as explicit and simple as possible to avoid 'creative accounting' practices.
* The UK has launched a similar system as part of the UK's mandatory climate change and energy saving scheme, but this uses relative changes in carbon emissions which it paradoxically calls an ‘absolute metric’. Another ‘growth metric’ can be reported which is linked to turnover, but this is still a relative figure. Surely an absolute figure per turnover would be more useful so one organisation can be compared with another in a similar sector. Of course there is no reason why relative change cannot be reported as well.
TECHNOLOGIES
5. Use of biochar stoves and universal particulate control technology on black carbon emitting appliances
Domestic biomass combustion is the second greatest contributor to net global warming after transport. This is partially caused by the black carbon emissions (part of smoke) released from burning this source. The atmospheric residence time of black carbon is only a few weeks, while CO2 emissions resides in the atmosphere for more than a century, so reducing black carbon emissions could quickly reduce climate forcing along with any potential feedback effects. Therefore, this is probably the most cost effective short term mitigation strategy available to us.
Biomass is commonly used for cooking in developing countries, often on open stoves producing substantial smoke which can cause health problems, especially if used indoors. Between 25 and 35 percent of the worlds black carbon from biomass comes from China and India alone. However, there is a smokeless method of burning biomass which has other benefits as well. If biomass is heated without the presence of air, it releases the smokeless, combustible gases methane and hydrogen, leaving a carbon or charcoal residue. Specially constructed biochar stoves can use this principle for cooking. The remaining biochar or charcoal left in the stove can be sequestered in the soil to lock away the carbon, or processed into a fertiliser. This biochar could be sold on by local communities, paid by a carbon tax on industrial emissions as described in item 4. Modern biochar production can also be industrialised in processes that may produce 3 to 9 times more energy than invested. However, it would be essential to ensure that the biomass was obtained from a sustainable resource and the commodity value is set at a level so it doesn’t encourage deforestation.
Substantial black carbon is also emitted from domestic fires and Diesel engines. Whilst road vehicle particulate emissions have been subject to stringent controls, this is not the case with stationary and off road Diesel engines which are often used for agriculture, mining and marine transport. A similar level of particulate control needs to be used on these appliances as well. This could be attained through a combination of in-engine technologies, after-treatment particulate filters and improvements in fuel quality. Since domestic log, peat and fossil fuelled fires are likely to remain inherently polluting at source, it is suggested that some type of after-treatment particulate control should be considered for these appliances as well, even on those used outside air pollution control areas.
6. Utilise vehicles more effectively and allow them to use a priority access infrastructure
Road transport is the largest contributor to net global warming of the human activity sectors examined in a recent NASA study, therefore, this should be another priority area for mitigation.
Despite all the technological advances in road vehicles to improve efficiency, the main factor determining the fuel consumption or carbon emissions per person carried is still passenger utilisation, or how full the vehicle is. A typical car will need to carry approximately 20 times the weight and 100 times the volume of the driver it carries. Carrying this much excess weight and space around is an inherently inefficient way of conveying people from one place to another. Similarly, public vehicles can be even more under-utilised than cars. This situation will continue until a more competitive and convenient method of public transport is found.
Utilisation in vehicles could be improved in two ways, by encouraging more people to travel in standard sized vehicles and reducing the size of vehicle to meet a typical journey load.
The first case can be met by developing nationally coordinated car-sharing schemes. Here, car drivers are guided to their destination, via small diversions if necessary, to collect and drop off passengers for a fee using priority access routes such as bus lanes. This allows drivers to bypass traffic jams in the rush hour and reduce their own journey times to make up for the lost time in picking up passengers.
The second case uses small, narrow width cars with the provision of a parallel road infrastructure. These vehicles might for example carry two people lengthways, seated back to back in a reclined position to minimise weight and air resistance. The parallel road infrastructure would consist of side lanes and underpasses, enabling drivers to bypass bottlenecks and reduce journey times.
7. Electrify the transport network and power it from overnight nuclear electricity
Battery Electric Vehicles (BEVs) exhibit no emissions from the vehicles themselves. However, emissions can be generated at the power stations that produce the electricity to charge their batteries, and the overall greenhouse gases emitted will be dependent on the energy generating sources used.
Most studies suggest that switching from Internal Combustion (IC) engined vehicles to BEVs would reduce carbon emissions, as well as improve local air quality. For cars in the UK, it is estimated that swapping from fossil fuelled to electric cars would reduce their carbon emissions by more than half, even when using the current methods of electric generation. However, further reductions in carbon could be achieved by generating more electricity from non-fossil fuelled sources. For example, any increase in nuclear capacity would be best directed towards powering BEVs, since these can be charged overnight and during other non-peak periods. Intermittent sources such as wind could also contribute since charging periods could be varied to match the windy periods.
While BEV range is limited without resorting to extortionately expensive batteries, most trips can be accommodated using relatively conventional batteries. Car trips in the UK involving journeys less than 80km in length cover 97% of trips and 75% of total distance travelled. However, for commuter drivers, trips involving journeys less than 80km in length cover 98% of trips and 88% of the total distance travelled. It is therefore suggested that for some categories of motorist at least, a basic BEV would be a practical and competitively priced proposition, especially as a second car. For longer journeys other alternatives could be made available such as replaceable SWAP modules or a ferrying system where cars are charged while being moved on a specialised car transporter.
Electric trucks and buses could also have their range extended by using an electrified guided trackway, built from underused parts of the rail network.
8. Introduce more incentives for improving energy efficiency in the housing sector
Home insulation grants are available in many countries especially for those on social benefits. However, the rate of implementation is very slow, and requires initiative on part of the property owner to act, so these measures will inevitably be delayed through apathy and inertia. This process could be speeded up using the following methods.
All property owners should qualify for free water tank, loft and cavity wall insulation and draught proofing. These should be heavily marketed to those owners with properties which exhibit a high heat loss visible through infra red imaging. The costs should be borne by a government interest free loan payable on the fuel bill for the property remaining with any new owner. If the repayment period is sufficiently long this should generate a continuous saving.
Less cost effective retrofit measures such as external cladding, internal wall insulation, heat pumps, condensing boilers, thermally efficient glazing panels and solar heating could be similarly encouraged, by the same mechanism, although a low interest loan should be used instead. On the other hand the least cost-effective technologies should only qualify for this incentive if they could demonstrate an economic payback period without the use of heavy subsidies. This might vary from location to location depending on the local environmental conditions.
9. Match supply and demand from sustainable energy generating systems
In a desperate attempt to meet renewable energy commitments, certain EU countries have engaged in widespread installations of large wind farms. While these can make a useful contribution to the electricity grid, and can be economically justified if situated in the correct locations, their usefulness is heavily compromised by their intermittency and unpredictability of output. Significant wind generation requires standby capacity from conventional fuelled generators during calm periods, this renders the whole grid system more expensive to operate since the efficiency of conventional plants are compromised by switching them on and off to meet the variability in supply of the renewable contribution.
These problems can be reduced somewhat by installing a continent-wide high voltage grid which can transfer electricity from remote areas where the wind is blowing, and using stores of hydro electricity and other renewable's when available. However, the disparity between supply and demand will remain problematic unless other initiatives are used.
One solution would be to use wind generated electricity to power heat pumps for space heating in all new build properties, and in particular offices. These buildings would be designed to use the thermal inertia of the walls, ground and underlying foundations as a heat store, so heat is retained during calm periods when there is only limited wind generation capacity. Hence the variable electricity generated from wind farms is effectively stored and released as heat helping to match the disparity between supply and demand.
Existing installations with air conditioning could also use heat pumps powered from electricity, but employ natural gas heating as a contingency during the calmer spells. It may also be possible to use hybrid gas and electric heat pumps to generate combined heat and power - see the article what is the potential of wind power? These initiatives would help to smooth out supply and demand and allow wind farms to be more economically used.
10. Ensure new power plants are carbon capture ready.
The inexorable increase in world demand for energy is disconcerting. China is increasing its electricity generation capacity by about 14% per year and has become the worlds largest direct emitter of carbon emissions, partially due to the widespread use of high-carbon emitting coal fired powered stations. To get this into perspective, Germany's entire electricity capacity of photovoltaics is equivalent to only 0.8% of China's increase in electricity generation per year (based on calculations using data here and here)
To stand any realistic chance of reducing carbon emissions, it is essential that we develop carbon capture and sequestration technologies for fossil fuelled power stations and industry on a large scale. However until we get these into operation, all new industrial units should be capable of being retrofitted with carbon capture technology and built near locations where the carbon dioxide can be stored.
Carbon sequestration and capture is neither the most popular, cheapest or the fastest acting option available, but this technology must be developed and installed as quickly as possible to give us at least a chance of controlling carbon from these plants; otherwise the developed world efforts at carbon mitigation will be heavily compromised.