Can anyone please help me in finding a suitable source of generating power using green technology for a iron casting industry?

We have an industry with a max load of 500kw. I like to use non conventional source of power to support my plant. What technologies we can use for generating the required power on site? This site has good solar power capacity but wind is not feasible as its not an windy area . But problem with solar photo-voltaic is the initial cost is too high. Is it possible to use waste heat recovery technique to generate power? Please suggest some latest technology for using in this plant. Currently we have 2 days power holiday imposed by our government due to shortage in power supply and it is affecting our working capacity.