daily storage dam damage fault damping down of the coke danger coefficient daughter daughter element daughter product day day-night tariff DC network d.c. network DC supply d.c. supply deactivation swimming-pool dead short deadweight tonnage dead well debris debutanisation debutanization decanted oil decant oil decay chain decay family decay product decay series decay tank decontamination dedicated battery dedicated low-voltage wiring deep mining deep opencast mining deferrable load deflected well deflecting force degree degree Celsius degree Fahrenheit degree Kelvin degree of coalification delayed automatic reclosing delayed neutron delayed neutron precursor delay tank delivery point delta-star transformation delta-wye conversion demand demand demand charge demand factor demand integration period demand rate demand set up demand tariff demonstration reactor demulsibility test dense medium density meter depentanizer depleted fuel depleted material depleted nuclear fuel depleted uranium depletion depletion charge depletion drive depletion member deposit deposition depressant depropanisation depropanization depth absorbed dose depth dose deresining derived energy

derrick DERV fuel de-silting sump desliming desliming screen destructive distillation desulphurisation desulphurization deuterium deuteron deuton developing fault development well deviated drilling deviating force dewatering dewatering pump dewatering screen diaphragm jig dielectric dry test dielectric wet test diesel fuel diesel index diesel oil difference number diffuser diffuse radiation diffuse solar radiation direct current direct current network direct current supply direct-cycle reactor direct fission yield directional drilling direct lightning strike directly-fired boiler directly ionising particle directly ionizing particle direct radiation direct solar radiation dirt discard discharge discharge current discharge current of an arrester discharge of radioactive materials disconnectable busbar discovery well discrepancy switch disintegration chain dispersion fuel disruptive discharge dissolved gas drive dissolved-gas drive dissolved natural gas distillate distillation distillery distilling tube distribution losses distribution network distribution of electricity distribution system distribution undertaking distributor district heating line district heating system disturbance recorder divergent reaction diversity factor Division for Natural Resources and Energy Doctor process Doctor sweetening Doctor treatment

dollar domestic appliance use domestic fuel oil domestic heating oil domestic tariff dose dosemeter dose meter dose ratemeter dose rate meter dosimeter double busbar substation double fault double line to ground fault dousing system downhole deviation drilling drawdown level dried gas drift mining drill collar spear drill hole drilling drilling fluid drilling mud drilling ship drilling sludge drilling string drilling vessel drill ship drill-ship drive driver zone droop of a set droop of a system dropping point drop point drum washer dry cleaning dry cooling tower dry distillation dry gas dry hole drying dry screening drywell dry well dry well dry year dual bore-hole technology dump duplicate supply dust duster