appropriate renewable hybrid power systems for the remote aboriginal communities

Appropriate renewable hybrid power systemsfor the remote aboriginal communities

Stephanie Jennings*, John Healey

Healey Engineering Pty Ltd, PO Box 21, Victoria Park, WA 6979, Australia

Abstract

Renewable power supply systems have been a natural choice for many of Australia'ssmall remote aboriginal communities where the costs of diesel fuel are high. The resultshave been mixed. This is partially due to design factors, but more importantly due to

community acceptance of these technologically complex systems and the maintenancearrangements with the community power station operators and local resource agencies. Thispaper looks at some of the issues to consider in the selection, design, installation andmaintenance of appropriate hybrid power stations for smaller remote aboriginal

communities. 7 2000 Elsevier Science Ltd. All rights reserved.

1. Introduction

Remote power systems have been seen as a clear market for renewable energy

technology with its ®nancial and environmental bene®ts. The reality in the remotecommunities is not as clear cut.

In theory, the renewable nature of the energy source has clear ®nancialadvantages over traditional fossil fuel technology in those regions. It also canprovide quiet, low maintenance power with no on-site pollution.

In reality, the reputation of solar and wind technologies in remote Aboriginalcommunities, in particular, is mixed. The main reasons are related to the selection

0960-1481/01/$ - see front matter 7 2000 Elsevier Science Ltd. All rights reserved.

PII: S0960 -1481 (00)00029 -X

Renewable Energy 22 (2001) 327±333

www.elsevier.com/locate/renene

* Corresponding author.

E-mail address: [email protected] (S. Jennings).

and design of the system for the location, clarity in contractor responsibilities, theoperator±control equipment interface and/or the level of community involvementor interest in the power station. Lack of attention or understanding of how toaddress these and other issues can lead to the disheartening, but all too familiar,end result of a diesel genset running continuously beside an abandoned hybridsystem controller and solar array that may still be fully functional.

2. A challenging environment for a new technology

The remote community is a challenging environment for designers and installersof new technology to work in. There are numerous geographical, social, culturaland environmental issues that are unfamiliar to many in industry. These are someof the principal pitfalls that those in the renewable energy industry must face.

The technology design and transfer needs to be appropriate for the cultural andsocial context. There are numerous issues to consider here. Movement of familiesbetween communities is considerable, as locals follow a ``modern-day'' nomadicexistence. This both impacts on load demand and training of locals in powerstation operation. In the remote communities, English is a second language formost of the local aboriginal population and illiteracy is high. So thought is neededin the written and verbal communication with the community, and discussionsshould work through the existing social hierarchy. There is little understanding ofelectricity by locals. Though their electricity needs are usually small, theirmanagement is erratic.

The remoteness of some of the communities is considerable and this will put thetechnology's reliability under test. When there is a fault, outside maintenanceassistance is far away and repair visits are costly. The added complication for asophisticated new technology such as an inverter/controller is that there is littleknowhow or equipment in the community to repair faults. So, if funds areavailable, a specialist is ¯own in or the equipment is trucked out to the city.Otherwise, what often occurs is that the inverter is switched o� permanently.

The bush environment puts most equipment under test, through widetemperature ¯uctuations, dusty conditions and lightning strikes. The full impact ofthe environment on new equipment is often discovered once the equipment isinstalled and operating.

A new technology, such as a solar hybrid power system, has to address theseaspects associated with technology's location. In Australia, there are numerousexamples of where this has not occurred and solar technology has been seen asless than successful. Despite this, renewable technology still has good supportwithin the remote communities. After all, it has strong arguments in its favourover the traditional fossil-fuel based power. It can supply clean, quiet, cheaperpower to these regions, reducing their dependence on an outside, non-renewableenergy source.

S. Jennings, J. Healey / Renewable Energy 22 (2001) 327±333328

3. Selecting an appropriate community power supply

Where possible, a visit to the community is an essential ®rst step. Selection anddesign of a system are liable to fail where there is no early face-to-face contactwith the community. Insight gained from an early community visit and meetingwith chairpersons can fundamentally change the initial ideas on power systemselection and installation. It also is important culturally and socially to gaincommunity respect and to provide a forum for input from community memberson their community's infrastructure. In order to communicate e�ectively withcommunity members, it is desirable to come equipped with some culturalunderstanding. This can be gained through reading references such as Forrest andSherwood [1].

From this visit, information can be sought on the following:

. community size and ¯uctuation;

. current power station infrastructure;

. average power demand and daily energy/fuel usage;

. daily and seasonal power/energy/fuel variations;

. level of household energy consumption;

. community growth, stability or decline; and

. proposed plans for new housing or community facilities.

At such a ®rst meeting, interest in renewable energy can be ascertained, as well ascommunity participation in construction work in the power station project.

Early indication of interest in renewable energy in the community is a keyfactor in the success of a future system. This interest, however, must go beyondone person, such as a community advisor or administrator who comes and goesfrom year to year.

4. Comparison of system options

An economic assessment of di�erent power supply options is needed thatcompares the lifecycle costs and initial capital costs. This can be done simply withnotepad calculations for small systems or using simulation programs [3] witheconomic spreadsheets, such as RAPSIM [2]. This provides an indication of keyparameters of fuel consumption and genset runtime of potential hybrid systemscompared to conventional diesel solutions.

In hybrid systems, the renewable contribution needs to be su�ciently high tohave an impact on both fuel e�ciency and diesel runtimes. Reduction in dieselfuel use and genset operation produces environmental and economic bene®ts ofless diesel fuel, lubricant, ®lter and coolant consumption and longer gensetlifetimes and maintenance intervals.

The current economic system still favours fossil-fuel based energy sourcescompared to renewable energy through rebates, hidden subsidies and lack of

S. Jennings, J. Healey / Renewable Energy 22 (2001) 327±333 329

costing of externalities in commodity prices. This a�ects the economic viability ofrenewable energy systems for large remote communities.

For these systems, with average loads above 15 kW, the lifecycle costs usuallyare not favourable for renewable hybrids compared with diesel-only systems. Theinitial capital costs also become prohibitively high. A small token renewablecomponent in these larger power stations has no bene®t, with increased systemcomplexity and negligible fuel e�ciency gains to be made. It can, however,provide the starting point for future renewable additions and if so, renewablepower regulators need to be appropriately sized from the start for this futurerenewable capacity.

Hence in the current economic climate, renewable-based power supply systemsgenerally have a market only in the small remote communities or outstations. This``new'' technology, however, is still not appropriate for all such communities. Anumber of factors come into play that will determine its success or otherwise,including:

. remoteness of the community from technical support/maintenance ÐRenewable systems are generally not suitable for extremely remote communitieswith no in-house knowledge of hybrid equipment, as system failure usuallymeans costly air ¯ights to the community by specialists or the system isneglected and switched o�;

. ability to connect a phone line to the power station Ð Remote access to thepower station switchboard is vital for reliable system performance andcommunity support during a changeover of community operators;

. cohesiveness and stability of the community Ð This often re¯ects itself in thepower station maintenance, as the local power station operators are valued bythe community and they take pride in their work. The adoption of a newtechnology such as a renewable hybrid system can depend on this for itssuccess;

. growth of the community Ð Rapid growth could quickly exceed the inverter'scapacity in a hybrid power station and so the power station operation becomesmore diesel genset-dominated. The longer term economic and environmentalbene®ts of a renewable system disappear as the renewables' e�ectiveness in thesystem is diminished;

. interest in the community for renewable power, as mentioned previously is aimportant criterion.

After these factors are considered, a simple manual genset system may be chosenor a certain type of renewable energy hybrid system. A range of renewable hybridcon®gurations are possible, however the choice must suit the community. Forexample, one possible option is a separate renewable DC power supply (i.e.without an inverter) for lights only, with a manual startup switch to the dieselgenerator(s) for larger AC loads. The genset could be kept o� for long periodswhen only lighting is needed, such as overnight. This simple renewable systemmay be suitable for a cohesive single-family community where there is an activeinterest and understanding of electricity production and use. In a larger


community, where 24-h power is required, an automatic renewable hybrid systemor generator only system may be chosen, depending on the factors above.

5. Designing the renewable hybrid installation

Again using simulation programs, hybrid and diesel component sizings can befurther re®ned and potential technical problems can be picked up. However, thedesigner should always return to ®eld experience to question the credibility ofsimulated results.

In the hybrid control and inverter equipment, the operator±equipment interfaceis critical. A simple, visual interface that does not depend on complex LCDdisplays is essential. A sophisticated, computerised screen and keypad is confusingand intimidating to the less-skilled operators and can be quite detrimental to thelong-term success of the system.

Within the controller and inverter, readily available componentry and easilyreplaceable circuit boards are ideal. This means failed boards can be replaced bylocal electricians, rather than specialists from the manufacturer or supplier.

Modular components are also desirable as opposed to tightly integratedpackages, especially in the medium to large systems. Separate genset controllers,station management controller and inverter with ¯exible interfaces are ideal asthey allow simpler upgrades and maintenance of the system.

Remote monitoring and control capabilities via a modem and phone line arevaluable features of a hybrid controller. Automatic fault dialout and loggingcapacity are also needed.

It is important to ensure the equipment is designed for the environment. Thisincludes the climatic factors of extreme temperature, high wind speeds, rainfallpatterns and high humidity, as well as lightning, dust and wildlife entry intocabinets.

In designing appropriate building infrastructure, care needs to be taken inproviding not only a safe but comfortable work environment for the operator.This often promotes community involvement in the power station, as well asgenerally enhancing equipment operation and lifetime.

As a guide to system design and safety requirements, the Draft AustralianStandard on Stand-alone Power Systems [4] is a valuable reference. It also sets outthe requirements for installation and maintenance of these systems.

6. Construction and handover of the power station

Precommissioning the equipment in the factory prior to delivery to site is animportant step that can save much time and expense in onsite problem solving. Itwould involve bringing together genset and hybrid technologies in the factory witha dummy load to test the operation of individual components and overall systemand iron out any controller di�culties with the hybrid equipment and diesel


gensets. Thorough testing is especially important if old equipment is to be used,which is in itself a risky approach that is not recommended.

Community involvement in some of the construction work is an option incommunities where there is an organised community structure and there areskilled people within the community or nearby. Local involvement in constructionwork may bring some direct ®nancial bene®ts to the project. However, moreimportantly, it has value in providing skills training and income to the communityand the potential for continuing involvement in maintenance of their communityinfrastructure.

Following construction, commissioning tests should be carried out with anindependent witness. The witness can observe the full range of tests and determinewhether the speci®ed system operation has been achieved.

Handover to the community should include a training component for a fewcurrent or potential local operators and perhaps sta� from a local resource agencythat assists the community. Clear visual instruction signs (without technicaljargon) on operational, maintenance and fault response procedure should bepermanently mounted to switchboard cabinets or other appropriate locations inthe power station.

A community awareness session on power station operation and communityenergy usage could be an option in some communities where a hybrid system isnew. Such a session could provide valuable knowledge and understanding in thecommunity of diesel runtimes and renewable energy contribution, as well as thelimits of this energy and how to manage this in the community.

As a minimum, 6-monthly maintenance of the hybrid equipment for the ®rstyear or two should be a part of the contract with equipment installers. Wherethere are multiple equipment supplier/installers involved, clearly de®ned contractorresponsibilities for maintenance and their equipment warranties will avoidarguments down the track on who is responsible to respond to an emergencymaintenance call-out.

An ongoing agreement is also needed regarding remote monitoring and control.This can be the shared role of the project manager and equipment manufacturerto provide remote assistance to local operators following the handover.

7. Conclusion

There are many pitfalls in the establishment of renewable hybrid systems inremote communities and there are numerous cultural, social and technical reasonsbehind them. People in the renewable industry, from managers to technicians,need to be aware of where the pitfalls exist and how to avoid them to ensure thesuccess of renewable applications in the bush. Then con®dence in renewableenergy technology can be gained and it will have a brighter future in remote areas.


Acknowledgements

Many of the ideas expressed in this paper were gained through work with OveArup & Partners as Contracted State Program Managers on the Remote AreasEssential Services Program funded by Aboriginal and Torres Strait IslanderCommission and Western Australia's Aboriginal A�airs Department.

References

[1] Forrest S, Sherwood J. Working with Aborigines in remote areas. 3rd ed. Perth: WACAE, Mt

Lawley Campus, 1988.

[2] Jennings SU, Pryor TL, Remmer DP. Combining simulation techniques and design expertise in a

renewable energy system design package, RESSAD. Solar Energy 1996;58(46):265±72.

[3] Pryor TL, Remmer DP. The use of simulation studies in the design of RAPS systems. In:

Proceedings of Energy, Environment and Economics Conference, Nov 20±24, Melbourne, 1995.

[4] Standards Australia. Stand-alone power systems, Draft, 1997.


appropriate renewable hybrid power systems for the remote aboriginal communities

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