The value of storage. Chris Elliott Senior Hydropower Engineer. 8 th November 2016

Transcription

1 The value of storage Chris Elliott Senior Hydropower Engineer 8 th November 2016

2 Overview Stroud, Gloucestershire Hydro is largest part of the business High and Low head systems Design Install Maintain Screening systems 1

3 Aims of Presentation Outline of the type of schemes FiT has encouraged Aside from FiT, where does a scheme s income come from? To what extent can water storage be added to a scheme to increase Energy capture Income per MWh generated Trends in prices leading from changes to generation mix and demand responsivity TRIADs Wholesale prices New battery storage technology

4 What types of scheme have been built under FiT Mainly simple high head, no storage under 15kW schemes 15kW to 100kW schemes 100kW to 500kW schemes 500kW to 2000kW schemes 2000kW to 5000kW schemes 2MW 194 schemes 25MW 362 schemes 54MW 137 schemes 83MW 70 schemes 4MW 1 scheme TOTAL INSTALLED CAPACITY BY PLANT SIZE 2000kW<Output<5 000kW 2% Output<15kW 1% 15kW<Output<100 kw 15% 500kW<Output<20 00kW 50% 100kW<Output<50 0kW 32%

5 What types of scheme have been built focus on high head, no storage Drivers Digression time pressures push developers to simple consents Lower impoundment heights Hard engineered intakes Fine screens Space constraints FiT income predominates storage is peripheral to economics Most FiT schemes don t have storage

6 Scheme income examples FiT payment does not have any time sensitive element Site pre accredited before 2014, 99kW size 75% FiT, 25% Other (Electricity, DUoS, TRIAD, REGO) Site pre accredited 2015, 500kW+ size 59% FiT 41% Other (Electricity, DUoS, TRIAD, REGO) Site pre accredited late 2016, 500kW+ size 47% FiT 53% Other (Electricity, DUoS, TRIAD, REGO)

7 Non FiTincome typical PPA, example 500kW scheme Electricity export TRIAD avoidance benefit GDUoS credits REGO c. 5p/kWh with time sensitivity 88,000 p.a. for 500kW scheme 45/kW typically with time and location sensitivity 18,000 p.a. for a 500kW scheme hitting 90% 90% GTPS Var. p/kwh location specific neg. If you have no storage: You are not able influence how well you hit TRIADs or maximise sale price intra day on a STOD tariff You are unable to avoid spilling once at capacity Therefore storage may increase both energy capture and /MWh

8 Energy capture improvement with active upstream storage 500kW plant, 150m head, 10000m3 storage 600 Power with no storage /kw /10/201400:00 19/11/201400:00 19/12/201400:00 19/01/201500:00 19/02/201500:0019/03/ :00 19/04/201500:00 19/05/201500:00

9 Energy capture improvement with active upstream storage 500kW plant, 150m head, 10000m3 storage Potentially look to introduce separate storage at convenient point upstream Topology Ownership Ecology No change to FiTaccredited scheme Relatively small impoundment, modest volumes May avoid Reservoirs act Generally lower risk structure Analogous to a mill pond rather than large dam

10 Energy capture improvement with active upstream storage 500kW plant, 150m head, 10000m3 storage Storage effect from summer storm /05/201519:12 03/05/201518:00 03/05/201516:48 03/05/201515:36 03/05/201514:24 03/05/201513:12 03/05/201512:00 03/05/201510:48 03/05/201509:36 03/05/201508:24 03/05/201507:12 Power /kw Stored volume /m3 Total power /kw

11 Energy capture improvement with active upstream storage 500kW plant, 150m head, 10000m3 storage 300 extra energy capture /kwh /10/201400:00 19/11/201400:00 19/12/201400:00 19/01/201500:00 19/02/201500:00 19/03/201500:00 19/04/201500:00 19/05/201500:00 Extra capture calculated to be 102MWh, value 17.1k p.a.* *=2015 pre accreditation Major pro certainty that this benefit will remain for life of FiT

12 Production time shifting with active upstream storage 500kW plant, 150m head, 10000m3 storage Typical STOD tariff structure (weekday) Nov Sep Jul May Jan Mar

13 Production time shifting with active upstream storage 500kW plant, 150m head, 5000m3 storage April flow duration and production from stored water Stored volume /m3 Movable production /kwh River Flow /m3s-1

14 Production time shifting with active upstream storage 500kW plant, 150m head, 1000m3 storage 1 Peak time capacity factor Monthly capacity factors 1600h to 1900h Monthly capacity factors 1600h to 1900h

15 Production time shifting with active upstream storage 500kW plant, 150m head, 10000m3 storage Value of shifting production Electricity value TRIAD value 1300 p.a 1300 p.a. Significantly higher where there is on-site demand Derived from aiming at maximising production 1600h 1900h on an all export STOD tariff Derived from increasing likely TRIAD capacity factor from 91% to 99%

16 Total current value of storage 500kW plant, 150m head, 10000m3 storage Minimise production loss from plant maintenance Capacity factor increase 17.1k Minimise wasted flow Generate at peak times Generate at peak time 1.3k Optimise hitting TRIADs 1.3k 19.7k Total benefit Constraints If you have a FiTaccredited site designed to have Qdesign Qmeanyou cannot scale up the plant because you lose FiT accreditation Reservoirs act volumes

17 Other situations where storage is significantly more valuable Existing storage If there is existing storage which can be adapted with relatively little additional regulatory and operational burden the benefit of storage can be enhanced On site usage Larger differentials between off peak export and import prices, and more time at this differential make this more attractive than working simply on export price differentials Flashy catchment Flashier catchments would usually lead to more than average spill and can benefit disproportionately from attenuating this Large design flow Grid services Potentially STOR market via aggregator

18 Batteries How come batteries are the in thing if we show that the business case for water storage is largely driven by gathering more FiTs Current storage capacity dominated by Hydro, but lots of hype around batteries and other storage technology

19 Storage revenue streams Response Enhanced Frequency Response Firm Frequency Response Reserve Fast reserve Short Term Operating Reserve Capacity Market Price / Time shift Transmission or Distribution cost avoidance Own use Curtailment Avoidance Price arbitrage

20 TRIAD changes OFGEM open letter TRIADs the three max demand HH / year result in apportionment of TNUoS charges TRIADs encourage demand reduction, but prediction getting too good, high users perceived to avoid fair share TRIAD avoidance via embedded diesel Distributed Generation (DG) at high users, and incentive not to just reduce on site demand, but export as much as possible Government would like to encourage new CCGT via capacity Market which is currently outcompeted by diesel DG But TRIADs are established and do lead to peak reduction, DNOs not clear on what latent demand there is Conclusion probably difficult to change probably hydro would not be badly hit by a broader base to transmission network charging

21 Overall conclusion on storage Water storage based storage can be cost effective especially with High head, flashy watercourse On site demand If you are considering a project Renewables First are a capable partner for assessment, design, delivery 20

22 Thanks for your attention 8 th November 2016