Grant Ellington North Carolina State University On-Farm Energy Assessment of New Curing Barns Grant Ellington North Carolina State University

LP Gas and Natural Gas Price Outlook $15 / MMBTU @ $1.10/gal $9.40 / MMBTU @ $0.75/therm Source: U.S. Energy Information Administration (LP Gas – Wholesale/Resale; N.G. – Commercial)

Variables Effecting Energy Consumption Barn energy efficiency (insulation, structural air leaks) Heat exchanger efficiency Burner firing rate Ambient temperatures Curing management Quantity of tobacco Quality of tobacco Curing energy efficiency quantified as pounds cured leaf per unit of fuel (lbs/gal LP)

Tytun

Long

World Tobacco

New Barn Specifications Long (10-box) Long HEx @ 350,000 Btu/hr World Tobacco (15-box) Evans HEx @ 500,000+ Btu/hr 2” insulated panels Tytun (14-box, 32T) Powermatic HEx @ 400,000 Btu/hr 4” insulated panels All fan motors 10 hp, 1-phase All barn pads insulated (3/4” blue board) Suretrol controllers

Foam Rubber Gasket Material Added to All Barns 2” x 1” Polyurethane foam or Neoprene/EPDM/SBR polymer – both with self-adhesive strip

Exhaust Gas Temperature (oF) Thermal Efficiency (%) Stack Gas Analyzer Results (Averages) World Tobacco Long Tytun Existing Long   2-Aug 29-Aug 16-Sep Barn Temperature (oF) NA 150 145 168 Exhaust Gas Temperature (oF) 575 616 601 312 355 345 352 370 369 360 387 Thermal Efficiency (%) 79.2 76.9 77.5 82.1 80 80.4 86.8 86.5 85.8 84.3 83.5

Temperature Profiles Cures 6-8

New Barn Cumulative and Daily Energy Usage (Cure 7)

New Barn Daily Fuel Usage (Cure 7)

Static Pressure Across Tobacco vs Time (Cures 4 & 5) lb/ft3 10.0 10.4 lb/ft3 12.5 12.2 12.0

Season Energy Efficiency Comparison

World Tobacco - (15 Box - 128 ft3) 2013 On-Farm Barn Performance Summary Cure Loaded UnLoaded Cure (hrs) LP (gal) kWh Green Wt. per Box (lb) Bulk Density (lb/ft3) Total Green Wt. (lb) Cured Wt (lb) lb Cured /galLP World Tobacco - (15 Box - 128 ft3)   1 19-Jul 26-Jul 168 319 1174 1300 10.2 19,500 2905 9.11 2 29-Jul 6-Aug 190 336 1381 1333 10.4 20,000 2888 8.60 3 7-Aug 14-Aug 275 1272 1536 12.0 23,000 4747 17.26 4 15-Aug 23-Aug 192 294 1294 3729 12.67 a5 24-Aug 2-Sep 213 223 1427 5097 22.86 6 3-Sep 11-Sep 174 311 5425 17.44 7 12-Sep 19-Sep 162 325 1281 1600 12.5 24,000 5470 16.83 8 20-Sep 28-Sep 184 316 1360 5691 18.01 (Avg. or Sum) 181 2,399 10,483 176,500 35,952 15.35 Long - (10 Box - 193 ft3) 278 1950 10.1 2908 10.46 b2 180 333 1442 2000 2904 8.72 164 272 1364 2350 12.2 23,500 4811 17.69 1470 3705 11.92 5 31-Aug 256 1443 2352 4993 19.50 314 1445 5393 17.18 18-Sep 1403 2450 12.7 24,500 5483 16.47 27-Sep 160 1462 5720 17.60 172 2,422 11,301 179,000 35,917 14.94 Tytun - (14 Box (32T) - 143 ft3) 25-Jul 156 267 1230 9.1 18,200 2847 10.66 5-Aug 161 283 1240 1429 10.0 2937 10.38 163 247 1290 1716 5088 20.60 22-Aug 158 248 1273 3790 15.31 b5 1331 1788 25,000 5268 21.24 9-Sep 141 286 1079 5828 20.38 146 300 1163 1859 13.0 26,000 5875 19.58 157 292 1256 1800 12.6 25,200 5825 19.95 2,171 9,862 183,400 37,458

Total Electrical (kWh) Existing DeCloet (13 Box) 2013 Energy Performance Summary Cures Avg. Cure Time (hrs) Total Fuel (gal) Avg. per cure (gal) Total Electrical (kWh) Total Green Wt. (lb) Total Cured Wt. (lb) lb /gal LP World Tobacco (15 Box) 8 181 2,399 300 10,483 176,500 35,952 15.35 Long (10 Box) 172 2,422 303 11,301 179,000 35,917 14.94 Tytun (14 Box) 156 2,171 271 9,862 183,400 37,458 17.26 Existing Long (10 Box) 6 206 *1,584 NA 9,127 132,500 23,849 13.25 Existing DeCloet (13 Box) 184 2,223 278 7,748 149,930 27,283 12.64   * 5 Cures

Energy Efficiency and Estimated Cost per Pound Cured Leaf (fuel only)   Fuel Cost ($/unit) 0.80 1.00 1.20 1.40 1.60 1.80 2.00 lb/gal $ / lb Cured 7 0.114 0.143 0.171 0.200 0.229 0.257 0.286 8 0.100 0.125 0.150 0.175 0.225 0.250 9 0.089 0.111 0.133 0.156 0.178 0.222 10 0.080 0.120 0.140 0.160 0.180 11 0.073 0.091 0.109 0.127 0.145 0.164 0.182 12 0.067 0.083 0.117 0.167 13 0.062 0.077 0.092 0.108 0.123 0.138 0.154 15 0.053 0.093 0.107 17 0.047 0.059 0.071 0.082 0.094 0.106 0.118

Summary New barn energy efficiency was approximately 22% higher compared to existing barns on average New barns purchased to replace aging curing infrastructure and to better handle existing production 5 barn manufacturers made and sold barns in 2013 Energy performance alone is not the single justification for purchasing a given barn make, but is an important factor Performance comparisons and competition should result in improving barn design Plan to continue work in 2014 and include additional barns

Acknowledgements NC Tobacco Research Commission Philip Morris International Altria Client Services Alliance One International Japan Tobacco International Lake Wendell Farming Co. Triple B Farms Scott Farms DMG Farms Patterson Farms Allen Newton Mac Grady Farms R.A. Wood Farms Dennis R. Wood