Second International Symposium on Fishing Vessel Energy Efficiency E-Fishing, Vigo, Spain, May 2012
Energy audits of fishing vessels: lessons learned and the way forward Oihane C. Basurko, Gorka Gabiña, Zigor Uriondo Marine Research Division, AZTI-Tecnalia, Sukarrieta, Spain.
Abstract—Commercial fishing activities are strongly fueldependent. Consequently, the dramatic increase in the price of diesel fuel has impacted negatively on the economic incomes of fishing. Moreover, the overexploitation of north-Atlantic fisheries, over many decades, has caused international regulatory bodies to establish more restrictive catch quotas, on certain commercial fisheries. Both the fuel dependency and the restrictive catch limitation have brought the Basque commercial fishing industry to its ‘survival limit’. To examine the situation, an energy audit methodology for fishing vessels has been developed, with two objectives: a) to make shipowners aware of the way fuel is consumed in their activities; b) help shipowners to reduce their fuel bill. This contribution provides an overview of the methodology, together with the steps undertaken for energy audits. Three fishing vessels (a stern trawler, a live bait purse seiner, and a troller have been studied, for developing this methodology. The methodology uses a combination of commercial tools, such as ‘GESTOIL’ (an onboard fuel consumption management system) to collect and assess data. The energy audit has served to highlight the areas of major consumption and potential savings; it provides also a list of recommendations to shipowners, for changes in the operational patterns of a ship. Likewise, structural changes to increase the fuel efficiency of a vessel. In order to improve the efficiency of future energy audits, the experience gained and the difficulties undergone are presented. Keywords: Energy audits, fishing vessels, energy consumption, best practice, experience learned.
I.
INTRODUCTION
Traditional fishing has been the economic driver for many coastal communities in the Basque Country. The increase in the fuel price, the stock decline, occupational risks of fishing, together with the possibilities of establishing a different future for newer generations, are some of the reasons that have made fishing arrive to its survival limits, in many parts of Europe. Fishing gears have evolved throughout recorded history; ships, nowadays, are more technological than ever before. Examples are the mechanisation of gear handling, improved
performances of vessels and motorization, computer processing for gear design, navigation aids, and fish detection technologies [1]. Shipowners have invested greatly in updating their ships with new technology; this has helped to fish more efficiently and increase the comfort and safety onboard. Despite fishing more efficiently, more technology usually implies a major fueldependency. This pattern has evolved in the fishing sector to account for about 1.2% of the global oil consumption; which entails approximately 134 million tonnes of CO2 emission into the atmosphere [2]. Whilst no mention has been made in policy or international agreements, such as in the Kyoto protocol, with regards to Greenhouse Gas emission from fishing, the quantities consumed and emitted by the sector are considerable. This conclusion may make policy-makers consider fishing in their future policies, as one of the strategies to combat atmospheric pollution. The fishing sector needs to cope with all of these challenges, present a solid behaviour and become proactive in response to the rise in the fuel price. This objective requires good energy management, including monitoring the engines and the energy consumption, redesigning ships, and reinvention of the way fuel is consumed onboard [3]. However presently, the bunker purchased is usually the only registry a fishing vessel maintains of their fuel consumption. Therefore, energy audits may play an important role in this approach, since they can detail how energy is consumed within a vessel. Likewise, an audit may highlight the areas of major consumption and potential savings, including structural changes and operational practices. Research and experiences are growing within the published literature in this regard [4-10]. Nonetheless, more work is required since few have implemented energy efficient measures onboard. The present contribution provides: the main results of an energy audit of three vessels (stern trawler, purse seiner, and a troller); likewise, the methodology developed in
AZTI-Tecnalia to undertake energy audits on fishing vessels and guide auditors on the process; and the experience gained and the difficulties undergone. The contribution ends with a list of recommendations for undertaking efficient energy audits. II.
ENERGY AUDIT OF THREE FISHING VESSELS
Three Basque fishing vessels were audited, comprehensively, during a year. The main details of the vessels analysed are listed in Table 1. The fishing gears analysed are representative of the main fishing gears used in the Basque fishing fleet: a stern trawler, a troller, and a purse seiner (operating with two fishing modalities: the purse seine and the life bait purse seine). TABLE 1. DETAILS OF THE VESSELS Vessel 1 Fishing gear Length overall (m) Length at waterline Displacement (dwt) Displacement (GT) Construction year Hull material
Trawling nets
Vessel 2 Purse seine and life bait purse seine
Vessel 3 Trolling line*
39
37
25.9
33.4
30
20
239.1
149
66.4
432
231
84.2
2008
2004
1995
Steel
Steel
Steel
Base port
Ondarroa
Orio
Bermeo
Main engine
1030kW 8cyl. 800rpm
1060kW 16cyl. 1600rpm
3 of 1500 rpm:
3 of 1500rpm:
493 kW 12cyl. 1800rpm 2 of 1500rpm:
Auxiliary engines
2 of 515kW, 1 of 59 kW, a shaft generator
420kW, 170kW, 112kW
Crew size
11
Target species
Mixed fisheries
15 Anchovy, mackerel, horse-mackerel, sardine (purse seiner); Tuna (Life bait p.s.)
Fishery
The Atlantic, VIVII-AVIIIabd zones
The Atlantic, A1 and A2 zones
The Atlantic, VII-VIII zones
Fishing period
Mid-Sept. until mid-July
Spring and winter (purse seine), Summer and autumn (life bait p.s.)
Summer and autumn
Downtime period
Beginning of July until midSeptember
Mid-December until mid-February
Mid-March until beginning of June
32kW, 20kW, a shaft generator 5
Tuna
*Vessel 3 combines three fishing modalities during a year: trolling line, gillnet and vertical lines. In this contribution, only the results of the trolling line are presented.
For the data collection, flow-meters, a portable electric power logger, energy meters and the ‘GESTOIL’ system (an
onboard fuel consumption management system) were used. All of the equipment was installed and fixed onboard, with the exception of the portable electric power logger that was used sporadically. The electrical power logger was used for three outputs: (1) to measure the power consumption of a particular piece of equipment or machinery; (2) to register the energy patterns of a particular piece of equipment or machinery, for that it was left onboard for the duration of a particular fishing voyage; (3) to check the quality of the electrical load and network (including the rate of harmonics and unbalance). Energy consumption of the main engine and the operational profiles of the vessel were collected with the ‘GESTOIL’ system. The operational profiles of the auxiliary engines were estimated from the data collected with the portable power logger and the fixed energy meter. The analysis included also the identification of the activity patterns, engine loads, engine usage patterns, and their associated energy consumption for each of the activities onboard. Such activities include: energy consumed while sailing; finding fish; fishing (e.g. for trawling it meant energy consumed during letting the net out, trawling, tacking the net), and whilst in port. Data regarding the energy-consuming equipment/machinery onboard were provided by skippers and chief engineers. These data were completed with onboard measurement of selected equipment/machinery, such as the refrigeration and freezing system, water pumps and the lighting by the electrical power logger. III.
RESULTS
A. Performance indicators Performance indicators are listed in Table 2. The detailed report and results are available in [11]. An interesting indicator in energy efficiency is the ‘fuel use coefficient’ which provides results in terms of litres of fuel consumed, per tonne of fish landed [10, 12]. Vessel 3 is the smallest in dimension, capacity and crew size amongst the three vessels. Purse seine is the most efficient of all the fishing gear studied, since it presents the best indicator in relation to the litres of fuel consumed, for the fish landed, i.e. 98 L/t. Considering tuna as a target species, the results indicate that trolling line and the life bait purse seine present a similar energy performance indicator (1080L/t and 1136 L/t, respectively). Further whilst, purse seining for pelagic species is the least energy-intensive of the three, the trawling is the most energy-intensive. The most realistic comparison would arise, however, when two vessels operating in the same fisheries and using the same fishing gear are compared. The results obtained are similar with the ones presented in [10] for the same target species and gear used. Regarding the fuel costs compared with the total costs of the vessel, trolling is the one presenting the lowest ratio (15.3% in comparison to the 30-40% for the other gears).
TABLE 2. PERFORMANCE INDICATOR OF THE VESSELS AUDITED (1 YEAR PERIOD) Vessel 1 Gear
Purse seine
Life bait purse seine
Trolling line
224
89
91
100
Mon-Sat (6 d/voyage)
0.8 day/voyage
15 days/voyage
20 day/voyage
841896 L/yr Fuel consumption L/h
Vessel 3
Stern trawl nets
Days at sea (days/yr) Average voyage pattern
Vessel 2
Main
66600 Aux.
Sail.
Fish.
Elec.
22.4 %
65.5%
178.4
162.2
L fuel/tn fish landed
Main
135150 Aux.
Main
49751 Aux.
Main
Aux.
Sail.
Fish.
Elec.
Sail.
Fish.
Elec.
Sail.
Fish.
Elec.
9.3 %
68.9%
15.1%
16.0%
81.8%
5.3%
12.9%
58.4%
30.6%
11 %
-
87.46*
6.3*
-
102.5
5.5
-
35.89
21.70
-
1646 L/t
146 L/t
1080 L/t
1136 L/t
Average RPM
789
686
-
1083*
600*
-
1150
600
-
1000
1200
-
Average speed (kn)
10.4
4.01
-
9.5*
0.9*
-
> 6.5
1
-
7
8
-
Engine usage (h/voyage)
26.1
93.3
-
12.0*
1.7*
190
45
117
258
Income (â‚Ź/yr) Fish landed (tonnes)
1550717
320830
429333
198268 â‚Ź
511.5
455.8
125. 2
43.8
% fuel consumption regarding 39.3% 33.7% 38.4% annual costs Main: Main engine Aux.: Auxiliary engines Sail. : % of energy consumed for sailing to, from or in between fishing grounds Fish: % of energy consumed during fishing activities (such as letting out and tacking the net, trawling, trolling) Elec.: % of energy consumed to power the machinery onboard *target species: anchovy. Manoeuvring time has been omitted
All of the fishing gears, with the exception of the trawling, consume the most fuel while sailing (Table 2): the purse seine and the life bait purse seine more than the 80% of the total fuel consumption by the vessel, and the trolling lines approximately the 60% of the total. In contrast, in trawling more than the 60% is consumed whilst fishing. These percentages present a strong impact on the energy efficient measures that will be formulated, to reduce the energy consumption. Thus, it is clear, that energy efficient measures should be formulated considering the vessel, fishing pattern and the fishing gear used. B. Energy-consuming equipment/machinery The variety of onboard equipment and machinery onboard is wide-range. Different equipment classifications can be found in the literature [4, 9, 13]. Nevertheless, a more systematic classification is proposed herein (see below). GROUP 1. Navigation equipment/machinery. Essential equipment for navigation, such as fuel pumps, water pumps for engine refrigeration, lubricating oil pumps, air compressor, and fans. GROUP 2. Refrigeration and freezing system. Essential machinery for the cooling and freezing systems onboard, such as water pumps for the condenser for cooling the hatchery of
15.3%
fish in life bait purse seiners, and water pumps for the condenser of refrigerators. GROUP 3. Equipment/machinery for fishing. Equipment onboard used for and during fishing and the management of the catch, such as suction pumps, and the net winch. GROUP 4.
Lighting. Interior and exterior lighting.
GROUP 5. Accommodation. Machinery related to living onboard the vessel, such as the kitchen tops, TV, washing machine, and oven. GROUP 6. Additional equipment/machinery. The remaining machinery, such as desalination plant, freshwater plant, and water pumps. The energy-consuming equipment and the machinery used in the vessels studied accounted only for 9-13% of the total fuel consumption for each vessel. The navigation machinery and the cooling system accounted, together, for 40% of the electricity consumption in the trawler, i.e. the same consumed by the machinery for fishing along. On the other hand, the navigation and the cooling system of the troller accounted for 70% of the total energy demand. Regarding the purse seiner and the life bait purse seine modalities, the demand varied with the modality, with lighting being the most demanding one, and with the machinery for fishing and additional machinery
onboard being second. The energy consumption related to each group is shown in Table 3. TABLE 3. THE DISTRIBUTION OF ENERGY-CONSUMING EQUIPMENT/MACHINERY
Trawler (%)
Purse seiner (%)
Life bait Purse seiner (%)
Trolling line (%)
Navigation equipment/machinery
20,2
3,4
2,2
41,9
Refrigeration and freezing system
20,0
5,2
6,6
28,3
Equipment/machinery for fishing
36,9
4,6
38,6
0,6
Accommodation
6,58
7,2
4,7
2,3
Lighting
5,07
16.3
16.9
3,9
Additional equipment/machinery
11,3
63.2
30.9
22,9
In Vessel 3, a shat generator is used to power the hydraulic pump for boarding the tuna from the sea. This requirement makes the percentage of the machinery and equipment used for fishing in trolling being very low. With a different configuration, this value is expected to be higher. Hence, it can be concluded that the energy demand is ‘fishing gear-specific’ and no generalisations can be made in this regard, i.e. unless two vessels operating in the same fisheries and using the same fishing gear are compared. C. Energy-efficient measures Several energy efficient measures are available for these vessels; some relate to improvements whilst the vessel sails; others relate to the technological improvement of the energyconsuming equipment/machinery. The most popular measures are the following [4, 9, 14, 15]: a) Improving the energy consumption while sailing: -
reducing the cruising speed to an economic level;
-
changing the propeller for a more efficient one;
-
painting with more efficient antifouling paint;
-
adding a bulbous bow to the hull structure;
-
selecting the best route; and
-
the use of sails
b) Improving the energy consumption of auxiliary machinery: -
introducing frequency converters for electric motors and parts;
-
changing the cooker to an induction cooktop;
-
changing some of the lights to LED;
-
switching off the unnecessary lights, in port;
-
cold ironing to reduce emissions and energy consumption while in port
The most common published in literature, for their impact on fuel efficiency, are, as listed in Table 4, being the ones influencing the energy performance whilst sailing or fishing (such as adding a bulbous bow, downsizing the engines, or changing the propeller for a more efficient one). These actions imply, usually, a structural change. Although their investment may be returned within a 5 year limit [4], the investment is frequently outside of the economic possibilities and/or too risky for many shipowners. Hence, those with a lower investment are considered herein (see below). a)
Adding energy management software onboard such as the ‘GESTOIL’ system.
b) Improving the energy consumption whilst sailing (see below). •
Reducing the cruising speed to an economic speed (15% saving). It must be noted, however, that a reduction in speed entails less time for fishing. Hence, the amount of fish landed would be reduced. In the trawler, for example, it was estimated that a reduction of a 1kn implied one less fishing set. The shipowner would need to consider the benefit of reducing the fuel consumption, in comparison to a reduction in income, due to the fish caught, if the voyage pattern needs to be maintained.
TABLE 4. ENERGY-EFFICIENT MEASURES (WITHIN A 5 YEAR RETURN) FOR THE THREE VESSELS ASSESSED Energy efficient measures From 10kn to 9kn Reducing Always sailing < speed 9.5kn Always < 8kn Adding frequency converters Use of LEDs Induction cooktop Total investment In 5 Possible years economic In 10 saving years
Vessel 1 L/yr Return saved (yr)
Vessel 2 L/yr Return saved (yr)
Vessel 3^ L/yr Return saved (yr)
45.322
0
-
-
-
-
-
-
13954
0
-
-
-
-
-
-
337
0
3812
1.2
1647
1.9
-
-
3861
3.3
841
4,2
400
5.3
3242
1.5
792
3.1
-
-
16291 €
5660 €
1296€
162653€*
54974€*
951€*
360287€*
115034€*
3198€*
Fuel price: 0.61€/L *Without considering the amount of time reduced for fishing and its economic implication. ^ Results are estimated for the case that the vessels use only the trolling line during an entire year.
c)
Improving machinery •
IV.
the
energy
consumption
of
auxiliary
Introducing a frequency converter for electric motors and parts (Vessel 1 - in ice-making machine compressor and water pump, and the water pump for the refrigeration of the main engine; Vessel 2 - ventilation system and water pump for the refrigeration of the main engine): a 25% saving in each case.
•
Changing the cooker to an induction cooktop: 50% saving
•
Changing some of the lights to LED (Vessel 1 only all the 18W fluorescent lamps located in the engine room; Vessel 2 and 3 - all interior 18W fluorescent lamps): 55% saving. RECOMMENDATION TO EFFICIENTLY AUDIT FISHING VESSELS
A. Auditing process The comprehensive analysis of the vessels, together with the interactions with shipowners, skippers, chief engineers and the particulars of the fishing seasons, have led to the development of an energy audit methodology. This methodology presents the steps of an energy audit in, a structured manner. Likewise, it may assist auditors in reducing the time to collect quality data and decrease the disturbance to the crew and shipowner, during the audit. The methodology is based upon the Spanish norm for energy audits [16]; on published literature [4]; and on the experience gained doing comprehensive energy audits. The methodology is: 1.
GOAL AND SCOPE. Select the vessel to audit and define the goal and the scope of the audit, together with the shipowner.
2.
ESTABLISH CONTACT. Get in contact with the interested parties (shipowners, skippers, etc.)
3.
1st VISIT ONBOARD. The first visit permits observing the general state of the vessel, the detection of health and safety risks, and obtaining an idea of the working conditions onboard, as well as the required technical equipment (appropriate measurement tools) and safety equipment to audit the vessel (whilst onboard).
4.
QUESTIONNAIRE. Before meeting the shipowner prepare a questionnaire with the data required. Send this questionnaire to the shipowner, to be filled up.
5.
SHIPOWNER’S APPROVAL. The energy audit will require periodical visits to the vessel, interviews and equipment installation onboard. Before any of these takes
place, the shipowner needs to give approval to all the aforementioned. The number of visits onboard should also be defined. 6.
RETURN THE QUESTIONNAIRE. Once the questionnaire is filled in, it will need to be returned to the auditors, to process the information.
7.
INTERVIEWS AND VISITS ONBOARD. The shipowner and the Chief Engineer should be interviewed and, if necessary, the oilers too. Engines and onboard equipment/machinery-related data will be collected during the onboard visits, through the aforementioned portable and fixed instruments. Collect data whilst the vessel is in port.
8.
INSTALLATION OF THE ‘GESTOIL’ (or similar) SYSTEM AND ENERGY METERS ONBOARD. The ‘GESTOIL’ systems may be installed onboard to assist in collecting reliable data regarding the energy profile of the vessel.
9.
ANALYSIS OF DATA. The data collected (measured onboard and provided during interviews) will be assessed statistically.
10. ENERGY EFFICIENT MEASURES. Several energyefficient measures will be formulated, to help to reduce the energy demand of the vessel. The physical and economic feasibility of each measure will be assessed also from the data assessed. 11. FINAL REPORT. The Final Report will detail the energy diagnosis of the vessel. The report will include: the goal and scope of the audit; the methodology followed; and the proposed energy efficient measures, for that particular vessel and working conditions. B. Additional recommendations Several recommendations are proposed that can help in the auditing process and the implementation of the energy-efficient measures. •
Talk to shipowners and try to convince them of the benefit of undertaking an energy audit.
•
Define the procedure of the audit with the shipowner, to make him/her aware of the steps that will be followed and the implications of each step.
•
The readiness of the ship is the priority. Most of the time, the auditor is the last on the lists of priority after the service engineers, electricians, etc. Make sure that the facilities needed are provided on time for the audit.
•
Be organised and have all documentations ready, before the visit onboard.
•
Undertake a visit onboard guided by the Chief Engineer, but carry out the interview in a place without any noise.
•
Talk to the skipper and find a way to get him/her involved in the energy-efficient measures (perhaps providing an extra for reducing the energy consumption of the vessel).
•
Small impact energy efficient measures are good too! Be realistic. Shipowners have gone through a huge technological change to improve onboard technologies. Introducing energy-efficient technologies do not always mean the incorporation of expensive technologies. There has to always be a solution, for all levels of budgets.
•
Discuss the results with the shipowner. The best measure may not be attractive for its implementation, as it may affect the fishing (e.g. the trawling door: whilst one door resulted in being the most efficient, the other one fished the best and had a slightly worse energy-efficiency. The latter one was selected as best). As such, the best option is that which considers all of the aspects together.
•
Be aware that many factors affect the registered data. Registering a comprehensive amount of data is very timeconsuming. In contrast, registering few data can provide you with an estimation of the energy consumption. However, results might be biased by: the weather and sea conditions at the time of the registration; the amount of bunker onboard; the position of the full fuel tanks; the tidal conditions (low, high), etc. Hence, 3 data samples are recommended as the minimum size for the main and auxiliary engines.
•
Measures on board provide a more realistic result, than approximation by the Chief Engineer. Human factor plays an important role in reducing the energy consumption on the vessel.
•
Some shipowners work onboard as skippers, Chief Engineers and crew. In these cases, implementing operational energy-efficient measures will be easier.
•
The fishing voyages of purse seiners, life bait purse seiners and trolling are irregular (in terms of length of fishing voyages). Extrapolating from a small sample may introduce a large error in the results. Therefore, fixed energy measuring tools are more recommendable than the mobile logger to collect data from the main and auxiliary engines. V.
CONCLUSIONS
Fishing is ‘fuel dependent’. The increase in the fuel price has made the future of this sector insecure. A proactive attitude and measures are needed to overcome the present difficulties. Energy audits may play an important role in this approach, to establish the energetic condition of the vessel and its activity. Whereas energy audits in fishing are limited, in shipping, they are common. Shipowners and shipping associations have become proactive and have started collective actions, research and implementations, which help combating the effects of climate change on shipping [17]. The fishing industry needs to be established at the same level. Besides having the problems
with the price of the fuel, additional problems may affect fishing in the future, e.g. the IMO’s regulation on greenhouse gas emission (Annex VI of MARPOL which is regulated by the Annex VI of MARPOL 73/78). Energy audits will permit an improvement in the pollution of vessels, to be in a better position to overcome additional legislation in the future. A methodology to undertake energy audits has been presented. Likewise, the main results of an energy audit along with the potential energy efficient measures have been showed also. These measures have been formulated for the three audited vessels; nonetheless, they can be considered for possible inclusion in all energy audits. However, it must be noted, that each vessel behaves differently, despite operating with the same fishing gear. Therefore, an energy efficient solution for one may not be adequate for another vessel. None of these technical recommendations is possible, without undertaking an energy audit of the vessel. Furthermore, purse seiners and trollers have very irregular fishing journeys. Hence, data collection would need to accommodate these irregularities. The minimum data required will not necessarily be the same for all cases. Sampling a minimum of three voyages is recommended, to achieve a realistic result. Likewise, installing energy meters and an energy management system, such as the ‘GESTOIL’ system, is recommended strongly for all vessels, but especially for purse seiners and trollers due to their irregularities (in terms of length of voyage). ACKNOWLEDGMENTS The work presented in this contribution has been supported by the European Fisheries Fund (ref. 351BI20090040). We would like to express our sincere gratitude to: the shipowners, skippers and crew of the three audited vessels for their helpful support in this project; to Iñigo Krug and Jose Mari Ferarios (AZTI-Tecnalia), for their knowledge and help during the data collection in the fieldwork; and to Prof Michael Collins (IKERBASQUE, Basque Foundation for Science, Fellow (PIE, UPV/EHU)) for his helpful comments. REFERENCES [1] [2] [3] [4]
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