Experimental investigation of the tractor engine performance using diesohol fuel Behdad Shadidi a , Talal Yusaf b,⇑ , Hossein Haji Agha Alizadeh a , Barat Ghobadian c a Bu-Ali Sina University, Hamedan, Iran b National Centre for Engineering in Agriculture, Faculty of Engineering & Surveying, University of Southern Queensland, Toowoomba, 4350 QLD, Australia c Tarbiat Modares University, Tehran, Iran highlights  Diesohol is a new fuel mixture (diesel and biotethano).  Tractor performance using diesohol results is comparable with diesel.  UHC concentration was decreased using diesohol.  CO 2 concentration was increased using diesohol. article info Article history: Received 29 November 2012 Received in revised form 29 May 2013 Accepted 8 June 2013 Available online 30 June 2013 Keywords: Diesohol Bioethanol Diesel engine Tractor engine Engine performance abstract Diesohol fuel is a mixture of diesel and bioethanol fuels in which the ratio of bioethanol is less than 15%. In this research work, performance of a tractor engine (Massey Ferguson 399) using diesohol fuel was investigated. In these circumstances, the concentration of UHC and CO 2 emissions in the exhaust pipe were measured and analyzed. The engine was run at several speeds (1600–2000 rpm). The obtained results reveal that, when using diesohol fuels, the power and torque of the MF-399 tractor engine are increased by 3.17–8.50% and 1.75–10.28% respectively when compared to diesel fuel. This is due to a rel- atively more complete combustion of ethanol because of its high oxygen content. The fuel consumption and specific fuel consumption are also increased by 7.32–15.81% and 4.37–7.44% respectively due to low calorific value of ethanol compared to diesel fuel. The analysis showed that when diesohol is used, the rate of UHC is decreased but CO 2 emission is increased. In brief, by using diesohol fuels, especially E6 blend in comparison to diesel fuel, engine performance and emissions are improved without any changes in engine structure for diesohol application. Ó 2013 Elsevier Ltd. All rights reserved. 1. Introduction Energy is the main input of industry and technology. Most of the world’s energy consumption is produced from petroleum, gas and coal. Today, environmental concerns, a steady increase in pet- rol prices and gradual depletion of oil reserves have prompted researchers to examine reliable substitutes for fossil fuels. Over the past 25 years, worldwide petroleum consumption has steadily increased, resulting in higher standards of living, transportation and trucking, and increased use of plastics and other petrochemi- cals [5]. In 1985, total worldwide petroleum consumption was 2807 million tons and in 2008, the figure reached 3928 million tons, with an average annual growth rate of almost 1.5% [4]. How- ever, the petroleum is a finite source for fuel that is rapidly becom- ing more scarce and expensive [9]. In addition, petroleum-based products are one of the main causes of anthropogenic carbon diox- ide (CO 2 ) emission to the atmosphere. The current transportation sector worldwide is entirely dependent on petroleum-derived fuels [3]. One-fifth of global CO 2 emissions are created by the transport sector [12], which accounts for some 60% of global oil consumption [15]. Around the world, there were about 806 million cars and light trucks on the road in 2007 [19]. These numbers are projected to in- crease to 1.3 billion by 2030 and to over 2 billion vehicles by 2050 [21]. This growth will affect the stability of ecosystem and global climate as well as global oil reserves. The pollution caused by auto- mobiles is known to be one of the major sources of air toxics in many urban centers around the world [2,24]. Because of these rea- sons, many extensive research works have been carried out or are underway all over the world to find optimum alternative fuels and renewable energies. The most significant advantage of these fuels compared to con- ventional ones is pollution reduction because of non-sulfur content and oxygen content [11,22]. Using alcohol as fuel attracted a lot of 0306-2619/$ - see front matter Ó 2013 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.apenergy.2013.06.011 ⇑ Corresponding author. Tel.: +61 7 4631 2691x1373. E-mail address: yusaft@usq.edu.au (T. Yusaf). Applied Energy 114 (2014) 874–879 Contents lists available at SciVerse ScienceDirect Applied Energy journal homepage: www.elsevier.com/locate/apenergy