* Corresponding author. E-mail addresses: mishra } r@hotmail.com (P.R. Mishra), jcjoshi@ces.iitd.ernet.in (J.C. Joshi) Solar Energy Materials & Solar Cells 61 (2000) 383}391 Design of a solar photovoltaic-powered mini cathodic protection system P.R. Mishra*, J.C. Joshi, B. Roy ER&DCI (N) A-5, Sector-26, Noida -201301, India CES, IIT Delhi, Hauz Khas, New Delhi - 110096 India Rahul Multi Disciplinary Research Centre B-3, CEL Apartment, Vasundhara Enclave New Delhi - 110096, India Received 1 March 1999; received in revised form 13 September 1999; accepted 20 September 1999 Abstract A mini cathodic protection (CP) system based on solar photovoltaic power source has been designed and tested in the "eld. It is concluded that such modular systems are well suited for CP applications especially in remote and hilly terrains.  2000 Elsevier Science B.V. All rights reserved. Keywords: Corrosion; Pipe-to-soil potential; Anode-bed 1. Introduction Corrosion protection in soil environment is very important for millions of miles of buried steel pipelines and millions of buried steel tanks used throughout the world for transport and storage of natural gas, fuel, chemicals and water. The corrosion rate of solids depends on moisture content, dissolved salt concentration, and drainage [1]. The common corrosion-prevention methods for pipe line and storage tanks are protective coatings, anodic and cathodic protections [2]. Anodic protection is suit- able with an active}passive alloy, which exhibits a broad range of passivity and a low passive corrosion rate. The required electrical equipment is complex and expensive to install and maintain. Thus, anodic protection is not widely used [3]. Cathodic protection can be applied to bare metal surfaces to protect them from corrosion. However, the current density required is often so large as to render the process 0927-0248/00/$ - see front matter  2000 Elsevier Science B.V. All rights reserved. PII: S 0 9 2 7 - 0 2 4 8 ( 9 9 ) 0 0 1 2 1 - X