Making the most of monitoring
July 18th 2006 Managing the supply requirements for a large portfolio of sites needs a clearstrategy for metering, data collection and data management that makes themost of what a flexible automatic monitoring and targeting (aM&T) system canprovide. South West Water has had such an energy management strategy formany years and has recently completed the first phase of the implementationof NEMESIS - an integrated, open-architecture aM&T energy managementsystem. The company is now ideally placed to provide quality information tomeasure and report its energy performance at all levels
South West Water (SWW) part ofthe Pennon Group provideswater and sewerage services tosome 1.6 million customers,predominantly across Devon and Cornwall,through a distributed network of 1600 poweredtreatment works and pumping stations linked by15 000 miles of pipe. The majority of the company'senergy requirement is in the form of electricity withannual NBP-corrected volumes at around 260 GWh.
SWW has a declared aim to buy electricity from sourcesthat have a reduced environmental impact and indeedalmost 6% of its needs are provided from self generatedrenewable energy using hydro and sewage gas CHPtechnologies. Of the purchased energy volumes, some93% of the portfolio is supplied under a flexible supplycontract arrangement with energy that is sourced fromgood quality CHP. Unlimited buys and sells in any blocksize across any traded contract are permitted; the onlyconstraint being that any financial position taken mustalways be backed by a physical position. Takingadvantage of the company's consistent load shape,agreed shape and risk components were negotiated withthe supplier enabling the entire volume requirement tobe treated as baseload. This considerably simplifies theprocess of buying the required blocks in the wholesalemarket to meet each month's forecast demand. In return,SWW have agreed to manage their demand within bothtotal volume and peak to base load constraints in themonth something which has been "surprisingly easy todo, with the right monitoring in place".
The company's annual targets are determined through areview of its energy volume requirements from which(after allowing for growth in some areas and specificefficiencies in others) the financial budget is set.Thereafter, the operations personnel are responsible forachieving or bettering the agreed volume targets whileprice variances and cost savings through any flexiblepurchasing activity are managed as a financial product.Actual energy purchasing is carried out by the in-houseprocurement department's energy management team.The whole process is managed under a riskmanagement structure comprising a quarterly RiskManagement (RM) committee which draws itsmembers from across the business and which includessenior managers and directors and a clear RM policy.
Away from flexible purchasing, SWW has a welldeveloped structure for energy management with anenergy user group, made up from site owners andoperators, which reports into an energy strategy groupwhich is attended by the functional managers of thebusiness units and is chaired by the operations director.Through this structure, all energy matters can bedebated and subsequently reported at Board level.
These groups are just part of an embedded energymanagement culture at SWW amply evidenced by thecompany's consistent success in achieving the CarbonTrust's Energy Efficiency Accreditation in both 2001 andsubsequently during reaccredidation in 2004 with ascore that had increased to 88%.
Capturing energy volumes across disparate import,export, self-generated and submetered sources requiresa flexible data management system, backed by joinedupcontracts which provide clear statements on roles.SWW's energy manager says that "we have worked hardto ensure that there are clear responsibilities in themetering and data process and have built uppositive working relationships with companies whoin my opinion are the best in the industry."
Half hour (HH) metering is installed at 400 sites andmany of these have maximum demands a long waybelow what is now just the imaginary 100kWthreshold "that is still far too prevalent within ourindustry we see significant management benefitswith half hour metering at sites with demands ofjust 30kW, if they have reasonable load factors".
The data collector reads SWW's half hour metersovernight and makes the data available during thefollowing morning for automatic download from asecure ftp site. NEMESIS automatically reads thisdata into a database for publication in a variety offormats over the corporate intranet via an activeservertechnology. The system has been extensivelydeveloped in-house and its use of a standard webinterface means that it can be accessed by themajority of employees which includes sitemanagers, supervisors and operators at their placeof work, without the need for the individualinstallation of expensive, licensed or hard-tounderstandclient-side software.
The data is also adjusted and consolidated tonotional balancing point (NBP) level for aconsumption report which shows the summatedoperations usage, highlighting daily volumevariances as well as providing a month to dateposition against our volume and load shapeguarantees. The same report can show site levelvariances and allows drilling down to viewindividual sites' HH data if required.
Equally, the system allows users to search for a site,by name or reference number, to view a 12 monthenergy report, showing energy volumes, profilesand targets, a breakdown of the charges, as well ascalculating the equivalent CO2 value to show theenvironmental impact of this energy use.
Our non-half-hour (NHH) electricity requirementsare purchased from a qualifying renewable energysupplier and supplied under one of threenegotiated quarterly tariffs. Mounting operationalefficiency pressures within the water industry overthe last 15 years mean that almost all of the NHHsites run unattended for all but a few hours a weekand this significantly compromises the ability of thedata collector to gather manual reads. Keen toaddress this data hole, SWW is embarking on a largescale trial to install 'smart' meters at 200 NHH siteswith remote reading capabilities via SMS or GPRSover GSM. The meters will be configured to satisfythe supplier's data requirements for billing purposesas well as providing data with differing degrees ofgranularity (up to HH in some cases, but with acommunications cost trade-off ) to SWW for theirown profile monitoring purposes.
Last year, SWW started looking in detail atbenchmarking its treatment efficiency bothbetween sites within the organisation and with otherwater companies as part of its involvement with theWater-UK Energy Manager's Forum. A benchmarkingsystem was implemented as part of NEMESIS whichautomatically compares the internally-held energydata with corresponding flow data stored within acorporate measured data archive. The benchmarkingsystem was the winner of the Pennon Group'sEnvironmental Award in 2005 and this year itsusefulness has been extended with the addition of acarbon efficiency 'label'which provides results using areadily understandable metaphor which will befamiliar to most energy users.
SWW has a declared aim to buy electricity from sources that have a reducedenvironmental impact and indeed almost 6% of its needs are provided from selfgenerated renewable energy using hydro and sewage gas CHP technologies More articles from WEE News Desk: | 
