Glendullan

In 1972 a second distillery with 3 wash stills and 3 spirit stills went up next door.^2,4,5 Until 1985 both ran side by side, and their spirit was blended together and sold as Glendullan single malt.^3,6,7 Difford's Guide notes such a whisky could not be sold as a single malt today, and German Wikipedia calls it a vatted malt.^3,6,7 In 1985 the original plant closed and became a workshop for distillery engineers, while 'Glendullan 2' kept running.^2,4,8

Guinness bought the Distillers Company Limited in 1986, and Glendullan passed to United Distillers.^4,5 In 1997 Guinness merged with Grand Metropolitan to form Diageo.^4,5,6

Whiskypedia dates an on-site bio-energy plant for spent lees, waste from whisky making, to 2014; its builder Clearfleau announced the handover on 17 August 2015.^4,9,10 A pipeline brings by-products from nearby Mortlach and Dufftown, and after a year Clearfleau said the plant cut the distillery's fossil fuel demand by 25 percent.^4,9,10

It has 3 wash stills and 3 spirit stills.^5,6,7 Diageo describes the stills as large and onion-shaped, and steam heats them.^1,4 Shell and tube condensers turn the vapour back into spirit.⁴ Fermentation lasts 75 hours in 10 washbacks, the vessels where it takes place.⁴ Whiskypedia lists 8 wood and 2 steel washbacks, while German Wikipedia gives larch wood.^4,7 Whiskypedia says the long fermentation and slow distillation give a character on the lightly fruity side of grassy.⁴ Diageo calls the new spirit light and delicate.¹ Its malt is not peated, and its water comes from the Goats Well Spring.