Large-scale Natural Refrigerant Heat Pump Market – Global Industry Size, Share, Trends, Opportunity, and Forecast. Segmented By Capacity (20-200 KW, 200-500 KW, 500-1,000 KW, Above 1,000 KW), By Natural Refrigerants (Ammonia (R-717), Carbon Dioxide (R-744), Hydrocarbons, Other Refrigerants), By End Use (Commercial, Industrial), By Region, By Competition Forecast & Opportunities, 2018-2028F