Original Article: Link
December 1, 2015
By Dr. Janaka Ratnasiri
In my recent article on “Treaty on climate change at Paris summit – Sri Lanka’s contribution” which appeared in The Island of Nov. 24 and 25, I presented possible carbon dioxide emissions from thermal power plants worked out for the period 2010-2030 under 3 scenarios as shown in the figure given therein. These emission scenarios were referred to as a) Business-as-usual, b) unconditional and c) conditional, which were elaborated in the above article of mine.
Submission of INDC from Sri Lanka
All countries were required to submit their Intended Nationally Determined Contributions (INDC) towards mitigating greenhouse gas (GHG) emissions, and the UNFCCC required that these targets should be transparent, measurable and achievable during the commitment period. It was noted that the submission already made by Sri Lanka and available in UNFCCC website were faulted and did not comply with the requirements set out by UNFCCC. Hence, the possible contributions from the power sector towards mitigating emissions were worked out by the writer to be included in Sri Lanka’s submission to the UNFCCC Secretariat, for consideration at the Parties’ Conference being held in Paris from November 30 to December 11.
When working out future emissions, one has to go by various assumptions as information on how a system will operate in the future is not known exactly beforehand. Since there was not much time available to work out these in detail, and to alert the authorities concerned with least delay, a simple assumption was made of having all the thermal power plants operating simultaneously, and this was mentioned in the article. It was also mentioned that the resulting values could be considered as the maximum possible emissions.
Amended emissions from power sector
I have now worked out the emissions after adjusting the operation of the power plants to match with the historical performance in the case of oil-fired thermal plants, and in the case of coal power plants their performance was adjusted to yield the output close to that given in the projected generation under base load forecast appearing in CEB’s long-term generation expansion (LTGE) plans. In this exercise, the plant factor was taken as 50% for the diesel and combined cycle gas turbines (CCGT) plants, as 15% for the gas turbines and as 70% for the coal plants, under all three scenarios. The only difference was that the thermal efficiency of conventional coal plants was taken as 33% under BAU scenario and 41% for low-emission super-critical coal plants under ‘unconditional’ scenario and as 50% for natural gas power plants under ‘conditional’ scenario.
The resulting emissions are given in Figure 1, according to which the CO2 emission in 2030 under BAU scenario will be 22.9 Mt, 17.7 Mt under ‘unconditional’ scenario and 11.7 Mt under ‘conditional’ scenario. These give 5.2 Mt or 23% reduction of CO2 under ‘unconditional’ scenario and 11.2 Mt or 49% reduction of CO2 under ‘conditional’ scenario, relative to the emissions under BAU scenario. The ‘unconditional’ scenario has to be executed by the country with its own resources while the ‘conditional’ scenario executed with external funding. While the Environment Ministry is responsible for making the submissions and its follow up, the Power and Energy Ministry is responsible for the actual execution of any changes in the power generation system. Hence, a close collaboration between these two ministries is essential for the country to meet these targets. I believe there is still time to submit a revised document to the UNFCCC.
Emissions from the transport sector
In Sri Lanka, more than the power sector, the transport sector burns more fossil fuel and hence, any effort to mitigate emissions should include the transport sector as well. Based on annual oil and coal consumption data given in the SLSEA database, the CO2 emissions from each sector were computed for the period 2010-2014. The average emissions for this period comprised 50% from the transport sector, while 37% came from the power sector. The rest came from industrial, commercial and domestic sectors. Unlike in the case of the power sector, there is no long term projection of energy consumption in the transport sector undertaken by any transport authority. Hence, any projections will have to be done by extending the historical consumption rates for the future.
Analysis of 2008-2012 data on diesel and gasoline consumption for transport shows their average annual growth rates as 8.2% and 4.9% respectively. Under the same growth rates, annual diesel consumption will increase from 73.8 Peta (1015) Joule (PJ) in 2014 to 157.5 PJ in 2030, while the annual gasoline consumption will increase from 40.1 PJ in 2014 to 142.0 PJ in 2030. Taking these as baseline data, a set of new consumption data could be worked out based on possible measures adopted to mitigate emissions which will not only save emissions but also save expenditure on fuels.
The 2016 Budget had made some concessions to encourage the use of environment friendly vehicles by levying only 2.5% of excise duty when “vehicles run entirely on solar, hydrogen or helium” are imported. This, however, baffles me as this is the first time I have heard of vehicles running on helium gas, which is the most stable gas not reacting with any other substance or burning to generate energy (I wonder who gave this information to the Minister!). Yes, there are vehicles on the road running on hydrogen in countries like USA, Germany and Japan where there is infrastructure to supply hydrogen to vehicles. But, Sri Lanka has a long way to go for that. Also there is the cost factor. A hydrogen operated Toyota sells currently in USA for about USD 57,000. May be some entrepreneurs could come forward to import these vehicles one day after setting up the necessary infrastructure facilities, provided the concessions will not be withdrawn later, as happened in the case of hybrid and electrical vehicles.
Options for mitigating transport emissions
What would have been practical at this stage is for Sri Lanka to allow the import of electric cars which are already in use in the country without raising its tax to 50% and to encourage the users to install solar panels on their house roof tops which qualifies for deductions for tax as provided for in the budget proposals. If the vehicle battery is charged during nighttime and the energy consumed is set off from the electricity generated by the solar panel during daytime using the net-metering system, it is virtually running entirely on solar and should qualify for the 2.5% excise duty. Under the circumstances, levying a 50% tax on electrical vehicles is totally unwarranted and defeats the Ministers own proposal. Shifting to electrical vehicles could have been included as an ‘unconditional’ measure for mitigation. However, the policies should not change from year to year every time the budget is prepared for such long-term programmes.
The other option that can be implemented in the transport sector is to introduce natural (NG) gas as a vehicle fuel under the ‘conditional’ scenario. If NG is imported to operate power plants as proposed in the previous article, the gas could also be provided to operate vehicles. NG operated light vehicles as well as heavy vehicles are found in many other countries and could be easily adopted in Sri Lanka, provided policies and regulations are in place and the price is competitive. However, it is pre-mature to work out the possible savings of oil based on NG penetration at this stage without a detailed study.
(To be concluded tomorrow)