Feasibility Study for Mobile Sorption Storage in Industrial Applications

Transcription

1 Feasibility Study for Mobile Sorption Storage in Industrial Applications G. Storch, A. Hauer ZAE Bayern Bavarian Center for Applied Energy Research

2 Motivation Aim: waste heat usage for better overall efficiency Basis: two feasibilty studies for waste incineration plant and aluminum plant This talk: main results in generalized form to show important trends

3 Outline 1 System description 2 Economics 3 Energy balance

4 Outline 1 System description 1.1 Heat distribution concept 1.2 PCM-storage 1.3 Sorption storage Economics Energy balance

5 Heat distribution concept Charging system Truck + Container Customer A Customer B Customer C

6 Technology: PCM TransHeat Schneider PCM mass 25 t (?) 22 t Container total mass 28 t 26 t Energy content / container 2.7 MWh (?) 2.4 MWh Thereof latent heat 1.8 MWh 1.6 MWh typ. load charging (90/70 C) typ. load - discharging (38/48 C) typ. load discharging (25/40 C) Energy losses? 320 kw (?) 250 kw 160 kw (?) 125 kw 275 kw (?) 220 kw ca. 10 kwh in 24h Other systems?

7 Technology: Sorption Storage Zeolite storage unit Built from standard freight container. Zeolite volume 18,7 m³ Zeolite mass 15 t Sorption bed thickness 0,8 m Sorption bed cross section 23,2 m² Maximum airflow m³/h

8 Technology: Sorption Storage Charging waste heat 150 C Ambient air 10 C, 6 g/kg 140 C 6g/kg Zeolite 35 C 40 g/kg

9 Technology: Sorption Storage Dependency between storage capacity and charging temperature: 0.28 SCZeo,heiz [MWh/t] T des [ C]

10 Technology: Sorption Storage Discharging building Low temperature heat, e.g. 15 C 25 C Ambient air 10 C, 6 g/kg Humidifier 15 C 25 C g/kg Zeolite C 0 g/kg Heat exchanger

11 Technology: Sorption Storage Dependency between output temperature and low temperature heat source : TZeo,out [ C] T NT [ C]

12 Outline 1 System description 2 Economics 2.1 Framework 2.2 Results 3 Energy balance

13 System boundary Mobile Storage charging system, container, truck, wages, fuel storage container hot, dry air warm water Energy costs (considered) Demand site docking station, heat exchanger, evaporative cooler Initial costs (not considered)

14 Reference System Utility electricity oil / gas / district heating Demand site heat exchanger, boiler, chiller, Energy costs (considered) Initial costs (not considered)

15 Entry values Energy storage density Specific costs for investment, depreciation scheme Utilisation ratio for charging and transportation system User load profile (peak load, usage intensity) Distance charging station demand site Labour intensity, wages Reference energy prices (gas, oil, district heating)

16 Investment Cost [ ] Depreciation [a] Charging station Transportation PCM storage Zeolite storage

17 Running costs Cost [ ] Fixed costs per year Transportation 55 per 100 km Labour 28 per hour

18 Parameter default values Parameter Value Utilisation 95 % Distance 10 km Storage capacity PCM 2.4 MWh Storage capacity Zeolite 3.1 MWh Charging time PCM 9.3 h Charging time Zeolite 6.5 h Peak load discharge PCM 220 kw Peak load discharge Zeolite 197 kw Full load hours discharge 8000 h/a

19 How many containers? standby 24/24 h utilisation? approx. 4/24 h Charging site utilisation ideally 24/24 h Zeo Zeo Zeo Zeo User A User B + User C, D,

20 Cost distribution PCM Zeolite 31% 0% 13% 25% Investment charging system Investment Container Investment transport 34% 4% 0% 10% 24% Investment charging system Investment Container Investment transport General fixed costs General fixed costs Running costs transport 9% 9% Sum: % Running costs transport labour 10% 11% 7% Sum: labour Charging heat Auxiliary energy

21 Results: utilisation

22 Results: distance

23 Results: storage capacity

24 Results: charging heat costs

25 Intermediate summary PCM technology yields lower net costs but lacks energy throughput due to charging time acting as a bottleneck Competitiveness with gas prices not reached Charging heat needs to be for free Main factors: storage containers and manpower costs High utilisation and close distances are essential

26 Possible improvement Upscaling for better utilisation of truck Special applications for Zeolite with high heat pump effect Better match between charging and discharging time enables same throughput with less containers Countries with higher ratio of energy prices to wages Detailed feasibility studies show potential for zeolite in drying applications.

27 Outline 1 System description 2 Economics 2.1 Entry values 2.2 Results 3 Energy balance

28 Flow Diagram Charging station waste heat 132% auxiliary energy, transport 10.5% Zeo useful energy 100% User Fuel 105%

29 CO 2 -Emissions [t/a] Zeolite Without mobile storage Gas boiler Auxiliary energy Transport

30 Final Conclusions Mobile energy storage with zeolite generally outperforms PCM technology Key factors are utilisation and wages Competitiveness difficult to reach, yet possible Best performance for drying applications Beneficial from an energetic point of view

31 The End Thank you for your attention! Questions?