Elsevier

Energy

Volume 78, 15 December 2014, Pages 535-542
Energy

Modelling electricity demand using the STAR (Smooth Transition Auto-Regressive) model in Pakistan

https://doi.org/10.1016/j.energy.2014.10.040Get rights and content

Highlights

  • This study estimates electricity demand function for Pakistan using the STAR model.

  • Electricity demand follows a nonlinear path if price uses as a transition variable.

  • The price of electricity is below the optimal level i.e. 4.32 in Pakistan.

  • The projected electricity demand would be three times those of today in 2020.

  • Continuous investment in power sector should be required to meet the future needs.

Abstract

This study attempts to estimate Pakistan's electricity demand by applying STAR (Smooth Transition Auto-Regressive) model. The covered study period is 41 years – from 1971 to 2012. The results show that the electricity demand follows a non-linear path if the real electricity price is used as a transition variable. We find that the average real price of electricity is below the optimal level. In addition, the electricity demand is primarily determined by the level of development. The forecast statistics reveal that for a presumed GDP (Gross Domestic Product) growth rate of 6 percent, the electricity demand would jump almost three folds in 2020 as compared to the demand in 2012. Owing to a weak relationship between electricity demand and its price, a strategy built on price escalation may not work towards curtailing demand. To meet the future electricity demand, the following measures are important: i) shifting energy mix from thermal to renewable ii) increasing power sector's efficacy iii) adopting an integrated institutional approach and iv) creating a culture of conservation and responsibility.

Introduction

Electricity – a key energy resource – is the backbone of development process. Industries, production, transportation, education, construction activities, households as well as large businesses and small entrepreneurs heavily rely on electricity power. The availability of electricity is central to economic growth resulting into Pakistan's prosperity and eventual sustainability. Severe electricity shortage turns out to be one of the major causes of Pakistan's current sluggish economic performance. In June 2013, the electricity shortfall reached 4250 MW per day with demand standing at 16,400 MW per day and generation at 12,150 MW per day. Through its negative impact on employment, trade, and poverty, the prolonged power crisis stands out as a key devastating factor in the dismal economic growth of the country [1]. Pakistan has suffered from low GDP (Gross Domestic Product) growth rates during the times of electricity shortage [2]. Sporadic power outages are impeding the industrial sector of Pakistan. According to the World Bank, approximately 75 percent of the firms in Pakistan have identified electricity shortage as a major constraint to their growth. These firms are facing 8.2 percent annual sales losses because of power outages.1 Around 40 percent of factories and industry units have remained closed, and nearly 7.5 percent of the labour force is unemployed simply because of the electricity power crisis.2

Studies on the power sector have highlighted bad governance, poor transmission, distribution losses, circular debt, and a large increase in the electricity demand as leading factors contributing to the persistent power crisis in Pakistan [1], [3]. There is an ever growing electricity demand that stems from urbanisation, industrialisation as well as expansion in agriculture and service sectors. Electrification in rural areas of the country and establishment of new households because of population increase and marriages are seen as other factors behind the increase in power demand. The urbanisation has increased at a rate of 3 percent per annum: the highest percentage of urbanisation in South Asia. The trend in village electrification also exhibits an approximate annual escalation of 8 percent per annum through the village electrification program of the government [2]. All the above-mentioned factors – among others – have led to an unprecedented increase in electricity demand.

The precise assessment of electricity demand always remains a critical concern for policymakers in Pakistan. There are a number of studies that have estimated the electricity demand function in Pakistan [4], [5], [6], [7], [8], [9], [10]. These studies have mainly employed a linear functional form for analysing the energy-economic growth nexus. These studies have considered only linear co-integration framework for estimating the energy demand model while ignoring the possibility of non-linear co-integration model that may lead to the misleading conclusion [11]. Various studies have shown that when a non-linear effect is incorporated into the estimation process, the explanatory power of an energy consumption-economic growth model is improved [12], [13]. This study also aims at adhering to the new trend.

The objectives of this study are the following: i) to estimate the electricity demand function for Pakistan using a non-linear estimation procedure ii) to determine the optimal level of electricity price, and iii) to project the future electricity demand under different growth scenarios. This study employs the STAR (Smooth Transition Auto-Regressive) model, the most important regime-switching model, to examine the relationship between electricity consumption, real income, and electricity price in Pakistan using time-series data over the period 1971–2012. Various studies have shown that use of the STAR model is an efficient non-linear approach to estimating the energy demand function [11], [12], [14], [15]. The STAR model captures the non-linear relationship between variables using a transition function in a continuous manner [12], [15]. This study contributes to the existing literature in various manners: First, to the best of the authors' knowledge, no studies to date have estimated the electricity demand function in Pakistan using the STAR model. Second, this study calculates the optimal price level for electricity. Finally, this study uses different growth scenarios to project the future electricity demand.

The paper is structured as follows: Section 2 provides an overview of the electricity sector in Pakistan; Section 3 summarizes the existing literature concerned with the electricity demand function; Section 4 explains the data sources, and sketches the modelling framework and estimation methodology; Section 5 presents empirical results and discussion; and, Section 6 concludes the whole discussion and suggests the policy implications.

Section snippets

Pakistan's electricity sector

Pakistan has faced an electricity crisis since its inception. In 1947, Pakistan had the capacity to produce only 60 MW for its 31.5 million population. In order to address the electricity shortage through institutional intervention, the WAPDA (Water and Power Development Authority) was established in 1958. WAPDA constructed two dams with the capacity of 4478 MW in the late 1970s to overcome the energy crisis. Pakistan continued facing power shortages even in the 1980s despite some haphazard

Literature review

There is an extensive literature available on the electricity demand encompassing Pakistan, region as well as the entire world. Most of it, however, is focused on the causal relationship between electricity consumption and economic growth indicating mixed results. For example, a few studies predict unidirectional causality running from output to electricity consumption [16], [17], [18], [19], [20], yet others suggest causality running from the electricity consumption to output [21], [22], [23],

Modelling framework

The electricity demand is determined by various factors such as growing population, extensive urbanisation, rural electrification, industrialisation, rapid growth in domestic demand, and rising per capita income. Among these, income, population, and energy prices are considered critical determinants of electricity demand [44]. The impact of real income on electricity consumption occurs through various channels. First, economic growth causes expansion in the industrial and commercial sectors,

Empirical results and discussion

The descriptive statistics of the variables are presented in Table 1. The analysis provides information on the mean range and the scale of the relation between the variables. The descriptive statistics show that the per capita average electricity consumption is 5.5 kWh and the average GDP per capita is 10.04. The average real price of electricity is 1.29 and ranges from 0.78 to 1.68. The correlation coefficient matrix shows that GDP per capita has a positive and significant correlation with

Conclusions and policy implication

The present study has estimated the non-linear electricity demand function for Pakistan using time-series data over the period of 1971–2012. The study has employed a logistic STAR (Smooth Transition Auto-Regression) model for estimation. Time-series properties show that all variables are stationary at first difference with the possibility of structural break. The estimation results show that there is a long-run relationship between electricity consumption, GDP per capita, and electricity

References (61)

  • A.H. Kani et al.

    Estimation of demand function for natural gas in Iran: evidences based on smooth transition regression models

    Econ Model

    (2014)
  • S.-H. Yoo et al.

    Electricity generation and economic growth in Indonesia

    Energy

    (2006)
  • J. Squalli

    Electricity consumption and economic growth: bounds and causality analyses of OPEC members

    Energy Econ

    (2007)
  • P.K. Narayan et al.

    Electricity consumption–real GDP causality nexus: evidence from a bootstrapped causality test for 30 OECD countries

    Energy Policy

    (2008)
  • H.-T. Pao

    Forecast of electricity consumption and economic growth in Taiwan by state space modeling

    Energy

    (2009)
  • A. Shiu et al.

    Electricity consumption and economic growth in China

    Energy Policy

    (2004)
  • Y. Wolde-Rufael

    Electricity consumption and economic growth: a time series experience for 17 African countries

    Energy Policy

    (2006)
  • J. Yuan et al.

    Electricity consumption and economic growth in China: co-integration and co-feature analysis

    Energy Econ

    (2007)
  • V.G.R. Chandran et al.

    Electricity consumption–growth nexus: the case of Malaysia

    Energy Policy

    (2010)
  • A.E. Akinlo

    Electricity consumption and economic growth in Nigeria: evidence from co-integration and co-feature analysis

    J Policy Model

    (2009)
  • A. Acaravci et al.

    Electricity consumption-growth nexus: evidence from panel data for transition countries

    Energy Econ

    (2010)
  • H. Gurgul et al.

    The electricity consumption versus economic growth of the Polish economy

    Energy Econ

    (2012)
  • S.-T. Chen et al.

    The relationship between GDP and electricity consumption in 10 Asian countries

    Energy Policy

    (2007)
  • S.A. Solarin et al.

    Trivariate causality between economic growth, urbanisation and electricity consumption in Angola: co-integration and causality analysis

    Energy Policy

    (2013)
  • M.L. Polemis et al.

    The electricity consumption and economic growth nexus: evidence from Greece

    Energy Policy

    (2013)
  • C.F. Tang et al.

    Exploring the nexus of electricity consumption, economic growth, energy prices and technology innovation in Malaysia

    Appl Energy

    (2013)
  • W.N. Cowan et al.

    The nexus of electricity consumption, economic growth and CO2 emissions in the BRICS countries

    Energy Policy

    (2014)
  • I. Arisoy et al.

    Estimating industrial and residential electricity demand in Turkey: a time varying parameter approach

    Energy

    (2014)
  • C. Hamzacebi et al.

    Forecasting the annual electricity consumption of Turkey using an optimized grey model

    Energy

    (2014)
  • A. Pielow et al.

    Modeling short-run electricity demand with long-term growth rates and consumer price elasticity in commercial and industrial sectors

    Energy

    (2012)
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