Synergy Grids. A. Smart Grids and Synergy Grids. B. Smart grids. As of 30/01/2011

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1 Synergy Grids A. Smart Grids and Synergy Grids This shrt paper is intended t prvide a ratinale and starting pint fr an explratin f a cncept we call Synergy Grids. This cncept is based n an extensin f a relatively wellknwn cncept called Smart Grids, which is currently the fcus f much intensive study in many cuntries. In rder t understand ur idea f Synergy Grids, we must first review the majr ideas and features behind the Smart Grid cncept. B. Smart grids A Smart Grid is an electric pwer netwrk that links generatrs and users f electric pwer in a new way, by adding intelligent electrnic cntrls and sftware t the system. The smart grid can cllect the ptimal amunt f infrmatin necessary fr custmers, distributrs and generatrs t change their human and equipment behavir in a way that reduces system demands and csts, increases energy efficiency, ptimally allcates and matches demand and resurces t meet that demand, and increases the reliability f the grid. The scial and technical benefits f a smart grid are reduced greenhuse gas and ther emissins, lwer csts, increased reliability, greater security and flexibility t accmmdate new energy technlgies, including renewable, intermittent and distributed surces. The issue f GHG emissins is key in driving climate change, and the fcus n electrical prductin ges t the heart f the issue, since cmmercial buildings in develped cuntries use the majrity f all electrical utput, and mst electricity is generated in very inefficient thermal pwer plants. Cmpnents f a Smart Grid may be defined t include: Electrical distributin netwrks; Energy generatin surces including: Traditinal fssilfuel r nuclear pwer generating statins; Large renewable pwer supply surces, such as wind, slar thermal r wave pwer; District r lcal renewable energy surces, including wind, slar and bimass cmbined heat and pwer (CHP);; Small intermittent pwer supply surces t and frm individual hmes and buildings; Netwrk sftware that ptimizes pwer demand and supply and prvides diagnsis f actual r incipient prblems with the line r with equipment; Pwer use cntrllers that are linked t individual appliances r equipment, and that have the ability t shave peak pwer demands by signaling linked equipment t turn itself ff fr a perid f time, r t reduce its pwer requirements; The scale f applicatin f mst Smart Grid prjects is smewhat undefined, but it appears that mst prject develpers are lking at reginal r subreginal areas; e.g. large areas with many thusands f custmers. Synergy Grids Page 1

2 Figure 1: cnceptual diagram a Smart Grid Ptential Smart Grid benefits fr utilities Avidance r minimisatin f pwer blackuts r disruptins because f netwrk resiliency (similar t internet); Inducing cnsumers t use pwer mre efficiently with respect t surces and peak perids; Reductin f peak lads Frm the tw factrs abve, reduced greenhuse gas emissins Stability f cnsumptin Maintenance f a high level f pwer quality thrugh the ability f identifying surces and characteristics f distributed pwer surces in the grid; Fraud detectin and preventin Benefits fr building peratrs and wners Assuming that building systems and equipment have interfaces with an external smart grid netwrk, benefits als ccur at the building level. Such gains culd be: Realtime lad and supply adjustment accrding t pwer generatin situatin; Realtime infrmatin n the surce f electric pwer (green r cnventinal) that allw building peratrs t use surces with reduced r n GHG emissins, and als t take advantage f shifting electricity rates, ptimize the scheduling and perfrmance f building and tenant systems (including electric cars), and t ptimize the way that ccupants use the building. Perfrmance data frm the grid can als frm the basis f emissins trading; Synergy Grids Page 2

3 An ability t exprt pwer that may be generated n site by, fr example, PV arrays r regenerative pwer captured frm elevatr braking; Higher level f pwer quality fr critical IT systems; Smaller sized building technical facilities that mean savings in investment and peratin cst. Perfrmance data frm the grid n GHG reductins can als frm the basis f emissins trading; Use f building peratin flws such as waste water t prduce energy Use f building functins as a variable in energy cnsumptin, fr instance anticipated r delayed cling r ventilatin Predictive systems can be linked t the grid Use f energy strage capabilities built in the building such as: Building thermal inertia r thermal strage Built in batteries r pwer strage Sprinkler water tanks as thermal strage. Brader extensins f the cncept: Malta depends entirely n freign fuel il fr the prductin f its electricity and a substantial prtin f the electrical utput is used fr the desalinatin f mre than half f its water supply. Malta is therefre develping a smart grid t cver bth electrical and water supply systems acrss the island. 250,000 interactive meters will mnitr electricity and water usage in real time, set variable rates and reward custmers wh cnsume less energy and water. C. Synergy grids Smart grids R&D has been fcused n the ptimizatin f electric pwer. One f the fundamental aspects f the cncept is the ptimizatin f supply and demand, thrugh cntrl and strage systems. If we develp the Smart Grid idea at a lcal scale, we may be able t deal with a wider range f issues and mre in depth; There are many ther neighbrhdscale systems that culd benefit frm ptimizatin. This wuld prvide an apprpriate framewrk fr develping strategies fr neighbrhd infill and renvatin prgrams that must reach very high levels f perfrmance. Such an integrated apprach at a lcal scale might mre lgically be called a Synergy Grid. Sme f the neighbrhdscale (zne) systems that culd benefit frm ptimizatin f supply and demand include: Buildings with a deficit r surplus f thermal energy; Buildings with a deficit r surplus f dmestic ht water; Buildings with a deficit r surplus f grey water; Buildings with a deficit r surplus f DC pwer; Buildings with a deficit r surplus f parking spaces; Owners f private electric vehicles with a deficit r surplus f DC pwer; Each f these urban subsystems culd benefit frm apprpriate strage systems, cntrls and algrithms fr ptimizatin f supply and demand, and distributin netwrks. Synergy Grids Page 3

4 A Synergy Grid, as we define it, wuld g beynd the current definitin f Smart Grids t include the fllwing elements within a small urban neighbrhd (here referred t as a Zne fr cnvenience). 1. The Smart Grid prpsals we have seen are silent n the tpic f space heating r cling, and the pssibility f thermal generatin in the zne (GSHP, CHP r bimass), as well as thermal strage in the zne t serve such thermal surces. This is especially lgical in the cntext f sme buildings prducing a heat surplus (captured thrugh heatrecvery ventilatin systems), while thers culd benefit ecnmically frm znesupplied heat. On the cling side, sme building peratrs may find it mre ecnmical t draw n a chilled thermal surce supplied frm the zne. We therefre see a need fr thermal mid- term strage f thermal generatin surces and a redistributin system f lw- temperature heating systems f buildings in the zne that have thermal deficits. As with AC and DC pwer, ptimizatin cntrls and sftware are essential t ptimize such a system. 2. Many mdern buildings make prvisin fr rainwater capture and grey water use, but sme (e.g. highrise) have relatively minimal pprtunities fr rainwater capture, while lw- rise buildings can prduce large amunts. There is therefre lgic in explring a znewide greywater and redistributin system fr all buildings in the zne. Such a system wuld filter and treat grey and blackwater within the zne befre strage. Again, ptimizatin cntrls and sftware are essential t ptimize such a system. 3. A similar case can be made fr a znewide system fr slid waste strage and recycling fr all buildings in the zne. 4. In large znes, a lcal transprt system shuld be cnsidered, as has been prvided in Masdar. This wuld be designed t perate in cnjunctin with central vehicle parking fr all buildings in the zne, with capacity calculated and cntrlled accrding different peak time usage patterns f different ccupancy types (e.g. peak use fr ffice and retail during the day, residential at night). 5. The rle f DC pwer is dealt with in sme Smart Grid prpsals, but usually in relatin t pwer cntributins by reginal renewable energy surces and with respect t plugin electric vehicles. The pssibility f DC pwer as a parallel system in a smart grid is ne that shuld be investigated further, in view f the pssible use f DC fr pwer strage, lighting and equipment. The usual disadvantage f DC is a high rate f pwer lss ver distance, but that prblem has been minimized in new highvltage systems, and in any case wuld nt apply t a lcal smart grid system. Surces f DC pwer include that prduced frm CHP, PV, wind pwer, bimass r ther renewable surce n site r in buildings in the zne (remember that sme buildings are better riented, r have cnfiguratins better suited fr slar). ). Prviding this at the zne level, as well as in member buildings, wuld ensure diversity f supply. 6. As in Smart Grid systems, DC pwer shuld be prvided fr vehicle recharging in the zne. 7. The strage f DC pwer wuld have t be an imprtant feature f a Synergy Grid, t stre pwer generated in the zne, and t stre ffpeak pwer frm utside surces, fr redistributin t ther buildings in the zne with a deficit. Of curse, as in Smart Grid prjects, excess DC pwer culd be cnverted t AC and exprted back t the grid. 8. We als prpse t explre the installatin f DC pwer systems in cmmercial buildings in the zne, perating in parallel with cnventinal AC systems t directly prvide pwer t lwvltage DC equipment. This reflects the greater availability f DC pwer surces and als the increasing prevalence f DCpwered systems in buildings, such as electrnic light Synergy Grids Page 4

5 ballasts and cmputer equipment. Such an apprach wuld greatly reduce ACDC cnversin lsses. A majr Japanese cmpany is reprtedly ready t prduce a parallel AC/DC distributin system fr buildings. Such parallel systems wuld represent a majr shift in systems thinking, and wuld als require that parallel lines f electrnic equipment be develped. All f these systems will require ptimizatin algrithms and systems, and a new frm f zne management t be successful. Figure 2: example f pssible Synergy Grid Synergy Grids Page 5

6 D. Research required 1 Csts and benefits v. scale f implementatin fr PV, slar thermal, thermal strage, DC strage; 2 Technical issues in parallel ACDC distributin systems; 3 Preliminary estimates f energy, emissins, water and cst perfrmance gains that can be made in a synergy zne relative t a building bybuilding and ccupancybyccupancy apprach; 4 Develping cntrl and allcatin strategies fr ptable, grey, strm and black water; 5 Regulatry issues related t DC pwer and greywater use; 6 Issues related t management structure, ccupant input needed fr peratins and likely ccupant behaviur; 7 Operating cst and incme mdels; 8 Identify case studies that apprximate at least sme f the cncepts being studied, and study aspects that were successful and thers that were nt; 9 Special issues related t new v. existing neighbrhds; 10 Special implementatin issues in existing neighbrhds linking technical systems t existing buildings; E. Anticipated benefits We have already utlined the benefits that are awaited frm the intrductin f Smart Grids. We see Synergy Grids as adding additinal energy and envirnmental benefits frm the integratin f ther systems, beynd what is currently planned. Perhaps mst imprtant are gains in resiliency, efficiency and quality f service. Mre detailed theretical and practical wrk is needed t test this hypthesis. Nils Larssn and Frank Hvrka iisbe, January, 2011 Synergy Grids Page 6