## This content will become publicly available on March 20, 2020

## An accurate bilinear cavern model for compressed air energy storage

## Abstract

Compressed air energy storage is suitable for large-scale electrical energy storage, which is important for integrating renewable energy sources into electric power systems. A typical compressed air energy storage plant consists of compressors, expanders, caverns, and a motor/generator set. Current cavern models used for compressed air energy storage are either accurate but highly nonlinear or linear but inaccurate. The application of highly nonlinear cavern models in power system optimization problems renders them computationally challenging to solve. In this regard, an accurate bilinear cavern model for compressed air energy storage is proposed. The charging and discharging processes in a cavern are divided into several real/virtual states. The first law of thermodynamics and ideal gas law are then utilized to derive a cavern model, i.e., a model for the variation of temperature and pressure in these processes. Thereafter, the heat transfer between the air in the cavern and the cavern wall is considered and integrated into the cavern model. By subsequently eliminating several negligible terms, the cavern model reduces to a bilinear model. The accuracy of the bilinear cavern model is verified via comparison with both an accurate nonlinear model and two sets of field-measured data. The bilinear cavern model can bemore »

- Authors:

- Univ. of Saskatchewan, Saskatoon, SK (Canada). Dept. of Electrical and Computer Engineering; Brookhaven National Lab. (BNL), Upton, NY (United States). Sustainable Energy Technologies Dept.
- Univ. of Saskatchewan, Saskatoon, SK (Canada). Dept. of Electrical and Computer Engineering

- Publication Date:

- Research Org.:
- Brookhaven National Lab. (BNL), Upton, NY (United States); Univ. of Saskatchewan, Saskatoon, SK (Canada)

- Sponsoring Org.:
- USDOE; Natural Sciences and Engineering Research Council of Canada (NSERC); Saskatchewan Power Corporation (SaskPower) (Canada)

- OSTI Identifier:
- 1501585

- Report Number(s):
- BNL-211414-2019-JAAM

Journal ID: ISSN 0306-2619

- Grant/Contract Number:
- SC0012704

- Resource Type:
- Accepted Manuscript

- Journal Name:
- Applied Energy

- Additional Journal Information:
- Journal Volume: 242; Journal ID: ISSN 0306-2619

- Publisher:
- Elsevier

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 25 ENERGY STORAGE; bilinear cavern model; compressed air energy storage (CAES); heat transfer; ideal gas law; thermodynamics

### Citation Formats

```
Zhan, Junpeng, Ansari, Osama Aslam, Liu, Weijia, and Chung, C. Y. An accurate bilinear cavern model for compressed air energy storage. United States: N. p., 2019.
Web. doi:10.1016/j.apenergy.2019.03.104.
```

```
Zhan, Junpeng, Ansari, Osama Aslam, Liu, Weijia, & Chung, C. Y. An accurate bilinear cavern model for compressed air energy storage. United States. doi:10.1016/j.apenergy.2019.03.104.
```

```
Zhan, Junpeng, Ansari, Osama Aslam, Liu, Weijia, and Chung, C. Y. Wed .
"An accurate bilinear cavern model for compressed air energy storage". United States. doi:10.1016/j.apenergy.2019.03.104.
```

```
@article{osti_1501585,
```

title = {An accurate bilinear cavern model for compressed air energy storage},

author = {Zhan, Junpeng and Ansari, Osama Aslam and Liu, Weijia and Chung, C. Y.},

abstractNote = {Compressed air energy storage is suitable for large-scale electrical energy storage, which is important for integrating renewable energy sources into electric power systems. A typical compressed air energy storage plant consists of compressors, expanders, caverns, and a motor/generator set. Current cavern models used for compressed air energy storage are either accurate but highly nonlinear or linear but inaccurate. The application of highly nonlinear cavern models in power system optimization problems renders them computationally challenging to solve. In this regard, an accurate bilinear cavern model for compressed air energy storage is proposed. The charging and discharging processes in a cavern are divided into several real/virtual states. The first law of thermodynamics and ideal gas law are then utilized to derive a cavern model, i.e., a model for the variation of temperature and pressure in these processes. Thereafter, the heat transfer between the air in the cavern and the cavern wall is considered and integrated into the cavern model. By subsequently eliminating several negligible terms, the cavern model reduces to a bilinear model. The accuracy of the bilinear cavern model is verified via comparison with both an accurate nonlinear model and two sets of field-measured data. The bilinear cavern model can be easily linearized and is then suitable for integration into optimization problems considering compressed air energy storage. This is verified via comparatively solving a self-scheduling problem of compressed air energy storage using different cavern models.},

doi = {10.1016/j.apenergy.2019.03.104},

journal = {Applied Energy},

number = ,

volume = 242,

place = {United States},

year = {2019},

month = {3}

}