Monitoring Industrial Energy and Carbon flows

For a proper assessment of the impact of global energy use on the climate system, consistent and reliable monitoring of energy use, energy related greenhouse gas (GHG) emissions and energy efficiency developments is of vital importance. This thesis aims to improve the monitoring of energy use, carbon dioxide (CO2) emissions and energy efficiency for the industrial sector. In the first part of the thesis, a methodology to account for CO2 emissions originating from the feedstock and other non-energy use of fossil fuels is developed and applied to the Netherlands. The estimate for the amount of carbon stored in synthetic organic chemicals differs significantly from the estimates in the official Dutch GHG inventory. It is recommended to adapt the inventory methodology making use of the results of this study. This work has also contributed to the development of new guidelines on GHG emission inventories that were recently published by the Intergovernmental Panel on Climate Change (IPCC). The second part of the thesis deals with energy statistics for the chemical industry. Detailed analysis of the company data used to compile the Dutch energy statistics revealed that, occasionally, chemical products have been included in the energy statistics, resulting in an underestimation of feedstock use of 33 – 75 PJ in the period 1995 – 2004, which is 1 – 2% of the total Dutch energy use. It was also found that the guidance given in the survey was unclear on the inclusion of energy conversions and that the complexity of the chemical industry has insufficiently been acknowledged. The results have been used to develop a new improved survey that is in use since 2007. In the third part of the thesis, a top-down monitoring methodology for industrial energy efficiency developments is developed and applied to the Netherlands. Annual primary energy efficiency improvements between 1995 and 2003 are estimated at 1.3% on average. The methodology could also contribute to cross-country comparisons of energy efficiency levels, because most of the data used is also available in other countries. In the final part of this thesis, bottom-up energy model for the petrochemical industry is developed. The total energy loss for the 68 processes analysed is estimated at approximately 1900 PJ primary energy in the year 2000 in Western Europe. These losses can be regarded as a good estimate of theoretical energy saving potentials. Process energy use and energy effects of reaction both contribute significantly to the overall energy loss and it is recommended to address the reaction effects, not visible in energy statistics, more explicitly in energy efficiency studies. This thesis makes clear that detailed analyses using combinations of data at various aggregation levels can reveal weaknesses in the methodologies used in the design and evaluation of energy and climate policy. It is strongly recommended to policy makers to give these kinds of independent checks a more prominent position in the design of future policies

Towards consistent and reliable Dutch and international energy statistics for the chemical industry

Consistent and reliable energy statistics are of vital importance for proper monitoring of energy-efficiency policies. In recent studies, irregularities have been reported in the Dutch energy statistics for the chemical industry. We studied in depth the company data that form the basis of the energy statistics in the Netherlands between 1995 and 2004 to find causes for these irregularities. We discovered that chemical products have occasionally been included, resulting in statistics with an inconsistent system boundary. Lack of guidance in the survey for the complex energy conversions in the chemical industry in the survey also resulted in large fluctuations for certain energy commodities. The findings of our analysis have been the basis for a new survey that has been used since 2007. We demonstrate that the annual questionnaire used for the international energy statistics can result in comparable problems as observed in the Netherlands. We suggest to include chemical residual gas as energy commodity in the questionnaire and to include the energy conversions in the chemical industry in the international energy statistics. In addition, we think the questionnaire should be explicit about the treatment of basic chemical products produced at refineries and in the petrochemical industry to avoid system boundary problems

Towards consistent and reliable Dutch and international energy statistics for the chemical industry

Consistent and reliable energy statistics are of vital importance for proper monitoring of energy-efficiency policies. In recent studies, irregularities have been reported in the Dutch energy statistics for the chemical industry. We studied in depth the company data that form the basis of the energy statistics in the Netherlands between 1995 and 2004 to find causes for these irregularities. We discovered that chemical products have occasionally been included, resulting in statistics with an inconsistent system boundary. Lack of guidance in the survey for the complex energy conversions in the chemical industry in the survey also resulted in large fluctuations for certain energy commodities. The findings of our analysis have been the basis for a new survey that has been used since 2007. We demonstrate that the annual questionnaire used for the international energy statistics can result in comparable problems as observed in the Netherlands. We suggest to include chemical residual gas as energy commodity in the questionnaire and to include the energy conversions in the chemical industry in the international energy statistics. In addition, we think the questionnaire should be explicit about the treatment of basic chemical products produced at refineries and in the petrochemical industry to avoid system boundary problems.