The Clean Development Mechanism has been instrumental in the development of a number of cogeneration projects around the world, but none yet in Yemen, where the scope for projects is certainly present. Lia Carol Sieghart looks at the role that cogeneration could play as part of efforts to reduce greenhouse gas emissions from the country.

The Kyoto Protocol was signed in 1997, at the 3rd Conference of the Parties (COP 3) to the Framework Convention on Climate Change (UNFCCC) in Kyoto, Japan. This treaty significantly bolstered the Convention by committing parties from developed countries, known as Annex 1 Parties, to legally binding limits on GHG emissions. They may also acquire emission reduction credits by taking advantage of the three ‘flexibility mechanisms’ defined under the Protocol.

These mechanisms are:

  • International Emissions Trading (IET)
  • Joint Implementation (JI)
  • Clean Development Mechanism (CDM).

    The latter is the only mechanism that involves developing countries. The CDM allows Annex 1 Parties (or entities from those Parties) to invest in project activities that reduce GHG emissions and contribute to sustainable development in non-Annex 1 countries.

    The CDM has seen an exponential growth since the Kyoto Protocol came into effect in 2005. The end of 2007 provided a milestone with the 100-millionth certified emission reduction credit being issued. In April 2008 the 1000th project, an energy efficiency project, was registered with the Executive Board. At present there are more 3000 projects in the UNFCCC pipeline.

    Nevertheless, the number of host countries playing a vital role is still very limited. The geographic dispersion of registered projects remains imbalanced. So far the main share of projects is with Asia and Latin America. Most projects are registered with India as a host country, followed by China, Brazil, Mexico, Malaysia and Chile. India and China in particular have been early movers and have grasped the investment opportunities provided by the CDM. The vast majority of projects registered are in the energy sector. Taking into consideration the projects under validation and those requesting registration, it seems that this distribution pattern will not change significantly during the first commitment period.

    There are many reasons why the CDM has so far fallen short of its full potential, many of which are country-specific while others are repeatedly reported from various countries. In the Middle East and North Africa (MENA) region 18 countries have ratified the Kyoto Protocol, but to date only 20 projects have been registered (Table 1). This amounts to ~2 % of the total of registered project activities.

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    The MENA Region population comprises about 6% of the total world population, almost equivalent to the population of the European Union. Most MENA countries are experiencing a rapid population growth. The region is economically diverse – the spectrum ranges from oil-rich economies to countries that are resource-scarce in relation to population.

    By 2050, the MENA countries will reach an electricity demand of the same magnitude as Europe (3500 TWh/y). In some of the countries, electricity demand is expected to triple from almost 1500 TWh/y at present to 4100 TWh/y in 2050. Correspondingly, the effects of climate change will become more severe. The fossil fuel-based power sector offers enormous potential for CO2 emission reductions, both through energy efficiency improvements in existing applications as well as utilization of state-of-the-art technology for new capacity additions.

    Given the surging growth in energy demand, the region needs to develop sustainable energy patterns, increase energy accessibility – particularly for marginalized populations in rural areas – and encourage efficient use of energy. Countries need to embark on a less carbon-intensive development path. Utilizing the CDM can provide a vital trigger in this process.

    CHP has a clear opportunity to expand quickly. CHP installations, by combining electricity production with a heat recovery system, provide reliable and cost-effective opportunities for GHG emissions reduction and an important contribution to meeting heat and electricity demand. Cogeneration projects also have the potential to bring energy efficiency measures to large industries in the region, while the MENA oil industry and refinery capacity offers further significant cost-effective potential for heat recovery and cogeneration.


    The Republic of Yemen lies to the south of Saudi Arabia, bounded by the Red Sea and the Gulf of Aden. The 2004 census recorded a population of 19.72 million, with an average annual population growth rate of 3.2 % and one of the highest birth rates in the MENA Region. Yemen remains one of the poorest countries in the world, and currently ranks 49 on the UN’s list of the 50 Least Developed Countries. Yemen’s GNI per capita is US$760, compared to, for example, US$12,510 in Saudi Arabia, US$23,990 in the United Arab Emirates and US$9070 in Oman2. According to the Country Social Analysis (2006) by the World Bank the GDP growth rate has been falling steadily in recent years. Inflation has been averaging at almost 12% since 2002, rapidly increasing the cost of living.

    The country, a non-OPEC member, is the smallest oil producer in the Middle East3. Nevertheless, the economy is highly dependent on the oil sector, with the country’s oil exports accounting for approximately 85% of export revenues and 33% of gross domestic product (GDP). Yemen’s energy use relies heavily on fossil fuels. Thus, there is potential to reduce GHG emissions in the energy sector, the oil and refinery industry and in the industrial sector.


    The 2001 First National Communication to the UNFCCC used 1995 as a reference year for Yemen’s GHG emissions inventory due to the high uncertainty of 1994’s information as a result of the April–July 1994 civil war. The total GHG emissions (CO2, CH4, N2O) of the country, in 1995, amounted to 18.7 million tonnes CO2eq, (CO2=11.4 million tonnes, CH4=128,000 and NO2=15,000). Taking CO2 removal into account, the total net emission of CO2 is 845,000 tonnes. These figures are exclusive of the emission from the international bunker (114,350 tonnes CO2) and from combustion of biomass (353,290 tonnes CO2).

    Yemen’s emission profile by gas type for 1995 shows that CO2 accounts for 61% of the total national GHG emissions (113,580 tonnes CO2), N2O 25% (465,700 tonnes CO2eq) and CH4 14% (269,400 tonnes CO2eq). Table 2 shows gas emissions by various sectors.

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    If we look at the industrial processes, there are many that create GHG emissions as a by-product of the process itself. Cement production generated the most emissions (99.3%). Other production processes with minor emissions are lime production, limestone use and soda use (food & beverages). The total GHG generated by these processes was estimated at 547,000 tonnes CO2eq, which accounted for 2.92% of the country’s total GHG emissions. The production of cement in Yemen in 1995 was 1,089,000 tonnes that resulted in CO2 emission of 543,000 tonnes CO2eq representing 4.8% of the country’s total CO2 emissions (energy sector, industrial processes etc), while it represents around 2.9% of the total GHGs.

    The CO2 emission from cement production was calculated by multiplying 1995 cement production (1,089,000 tonnes) by the emission factor (0.4985 tonnes of CO2 per tonne of cement produced). The SO2 emitted from cement production was obtained by using an emission factor of 0.3 kg SO2/tonne cement, thus leading to 330 tonnes SO2 in 1995.


    Yemen’s 100% state-owned Public Electricity Corporation (PEC) formed in 1991, under the Ministry of Electricity, is the sole public utility with the mandate for generation, transmission, distribution and sale of electricity in the country. The entity operates approximately 80% of the country’s generating capacity as part of the national grid. The remainder is generated by small off-grid suppliers and privately owned generators, predominantly in rural areas4. In urban areas diesel generators are also used as back-up systems. The efficiency of diesel generators can be up to 40%. Electricity demand amounted to 3294 GWh in 2005, an increase of 9.6% annually since 2000.

    The Yemeni population has the lowest access to electricity in the region, with only 53%5 of the total population having access. Of the 72% of the Yemeni population living in rural areas, only 23% have any access to electricity, which compares unfavourably with 85% of the urban population that have access to electricity. Out of this 23%, about 10%–14% is connected to the national grid system while the remainder is estimated to have some access from other sources, typically a diesel generator that operates only a few hours in the evening. Even for those connected to the grid, electricity supply is intermittent, with regular rolling blackouts in most cities.

    Figure 1. Yemen’s total GHG emission in tonnes CO2eq by sector, 1995
    source: first national communication to the united nations framework convention on climate change, government of yemen (2001)
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    Yemen has been experiencing a chronic power supply shortage. An estimate for the electric power deficit in 2006 was 220 MW, a figure that is expected to increase to 250 MW in 2008. With the 2005 increase in diesel prices, the cost of diesel generation has become economically unsustainable thereby significantly increasing the demand for a lower-carbon, more-efficient, lower-cost and reliable energy future.

    The Poverty Reduction Strategy Paper (PRSP, 2003–2005) states the following: ‘Indicators show the failure of electric power in Yemen in keeping pace with demand [is] due to the ageing of the power stations and the distribution networks, which is reflected in the high losses that are currently estimated at about 38%, well above the internationally prevailing levels. This situation prevents the full utilization of machinery and equipment in the different productive and service units, or burdens the private sector facilities with the cost of setting up their own generating plants, not to mention the inability to systematically fulfil domestic lighting requirements. This situation is expected to continue over the medium term due to the increase of demand at high rates, and thus increases the adverse aspects on investment opportunities and the growth of output, income and employment, clearly showing the importance of strategic investment by the private sector in this field.’

    In the industrial sector, power is purchased either from the national grid or off-grid from privately owned diesel generators with poor electrical efficiency ranging from 25% up to 35% especially in light industry. Heavy industry, e.g. the cement sector – the most energy intensive of any industry6, covers its heat needs using boilers fired either by heavy fuel oil or diesel, again with an overall poor fuel efficiency. The main electricity consuming sections in a cement plant are the mills (finish grinding and raw grinding) and the exhaust fans (kiln/raw mill and cement mill) which together account for more than 80% of the total electrical energy usage.7 The separate production of heat and power is an obvious waste of energy. Change is needed by using a range of existing and emerging technologies, particularly in relation to the production and consumption both of heat and electricity.

    The cement industry is considered as one of the main players in the industrial sector. Commercial production started back in 1973 with the launching of the first production line of the Bajil Cement Factory. Cement production is highly competitive, both locally and internationally, so any improvements in production efficiency can result in important increases in competitiveness.8

    Despite 16.9 trillion cubic feet (tcf) of proven natural gas reserves, a cleaner source of non-renewable energy, heavy fuel oil or diesel-fuelled power generation remains the energy source. Use of natural gas is hampered by the absence of a domestic natural gas infrastructure. On the downstream side there is a crude refining capacity of 130,000 barrels/day from two ageing refineries. The Aden refinery has a capacity of 90,000 to 120,000 barrels/day, while the capacity at the Marib refinery, is 10,000 barrels/day.

    So the challenge for the government is to meet the energy needs of the country in an economic and environmentally sustainable manner. To address this challenge, one approach is to integrate the use of CHP as part of a larger portfolio of low-carbon energy technology solutions. Also the First National Communication under the UNFCCC suggests CHP as a viable measure to reduce GHG emissions and to cope with climate change.


    The Yemeni electricity sector driven by fossil-fuelled power generation is characterized by a loss of waste heat and a deficient transmission and distribution system resulting in poor net generation. Energy use and efficiency are important factors for economic development and environmental integrity.

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    CHP applications could be viable and cost-effective in the Yemeni setting because they:

    • reduce energy-related carbon dioxide emissions
    • provide a decentralized energy source which results in reduced investment in energy system infrastructure
    • reduce transmission and distribution losses.

    Energy-intensive industrial sites such as oil refining, heavy processing (food and textiles) and the cement industry with its simultaneous demand for heat and power, could all benefit. Also the commercial and institutional/residential sectors could match their thermal and electrical needs. CHP application in the commercial/institutional sector could address light manufacturing, hotels, hospitals and large office complexes.

    Despite good potential for CHP, to date no systems are operating in Yemen. The main barriers are: technical, financial, lack of maintenance capacity and awareness, the heavy subsidy of petroleum products and the absence of a domestic natural gas infrastructure – the fuel of choice for most new industrial CHP systems. However, access to reasonably priced and reliable electricity supply systems are an obvious prerequisite for economic stability and development. The development of a strategy for CHP would assist in kick-starting the momentum in Yemen and should include the following elements:

    • identification of projects that could be initially implemented by the public sector and identify pipeline of projects that can be promoted for private sector development
    • formulation of CHP-enabling market
    • elaboration of incentives that attract private investors and lower the costs of electricity generation from CHP applications.

    Coupling GHG emissions abatement with CHP installation would help guide the country’s economic growth to a less carbon-intensive development path. The emission reduction potential makes CHP applications, in principal, eligible for the CDM. In order to qualify for Certified Emission Reductions under the CDM, one needs to address ‘additionality’, ‘permanence’, and ‘leakage’ requirements as well as satisfy sustainable development criteria defined by the country. By gaining CDM support for projects, Yemen could gain access to significant additional flows of technology and finance to assist in achieving a more sustainable, less greenhouse-intensive pathway of development. Also the National Adaptation Programme of Action9 is suggesting CHP systems as an efficient method of power generation and a suitable measure to reduce GHG emissions. Considering a cogeneration project as a CDM project activity would assist in generating emission credits and thereby make the project more feasible.


    The CDM is a key model fostering broad engagement in climate change mitigation, and can be used as a means of promoting sustainable development by providing access to improved energy services. The energy sector is a major source of GHG emissions and a critical area for socio-economic development of the country. Yemen has a good potential for cogeneration projects in the industrial, commercial and institutional/residential sectors.

    In keeping with the dual aim of climate protection and sustainable development, the CDM can trigger the installation of CHP systems by removing barriers to implementation of state-of-the art technology in this area. Despite the strong potential of cogeneration for GHG reduction to date there is no installed capacity – project developers often lack the technical and financial capacity to identify projects within their operational activities. Mainstreaming carbon finance into business operations would have a catalytic impact on facilitating CDM project development and consequently assist in the feasibility of cogeneration in Yemen.

    Lia Carol Sieghart is with the Ministry of Water and Environment, DNA Secretariat, Republic of Yemen.


    1. Status: 29.03.2008

    2. World Development Indicators database, World Bank, 1 July 2007

    3. Report No.: 34008-YE – Republic of Yemen – Country Social Analysis – January 11, 2006 – Water, Environment, Social and Rural Development Department, Middle East and North Africa Region

    4. Energy Information Administration ( Yemen – Country Analysis Brief (October 2007)

    5. World Bank and UNDP (2005): Household Energy Supply and Use in Yemen: Volume I, Main Report

    6. WADE (2007): Concrete Energy Savings – Onsite Power in the Cement Industry

    7. IPPC (Integrated Pollution Prevention and Control). 2001. Reference document on best available techniques in the cement and lime manufacturing industries, European Union.

    8. WADE (2007): Concrete Energy Savings – Onsite Power in the Cement Industry

    9. 2001 First National Communication to the United Nations Framework Convention on Climate Change