Wave Powered Malts?

Low carbon distilling… beyond steam… the changing the character of spirit… a unique opportunity for new and small distillers

It’s clear that the distillery of the very near future will be different to the fuel oil drinking, steam eating behemoths which currently dot the highlands and islands.

Many distilleries will have to make two significant changes; new fuel sources will be used to provide heat and power, and they will have to use that power in more efficient ways. Distilling will have to turn away from steam and towards low pressure, low temperature systems.

Low pressure, low temperature distilling

The optimum design for any building depends on where it is and what resources are nearby.

We designed Ardnamurchan and NcN’ean distilleries which both use biomass from nearby forests. Instead of being exported they are chipped and burned locally. Biomass is green fuel, but this is still burning stuff to make conventional steam. However steam is not the only method of heat transfer for distilling…

The answer to low carbon distilling lies in using less energy, making and wasting less heat. One way of doing this is to use thermal fluids.

Thermal fluids have been used for years in pharmaceutical, brewing and refinery plants. The use of thermal fluids allows for more compact production plants, thereby saving on space taken up by boilers. Unlike steam systems these are unpressurised, so the safety regime associated with high pressure systems is no longer necessary.  

By using thermal fluids within a distilling system based around a hot well – a large thermal store – alternative fuel sources can be used which are generated locally. The resources of each area can be used to heat the hot well at the heart of the process. This central point also acts as a heat sink for heat which is reclaimed through the process rather than being wasted, as is the case at conventional steam-based distilleries.

Power from nature

Any number of energy sources can be used when there is less demand for very high temperatures.

The island of Islay is an island of distilleries. It is surrounded by waters which have some of the strongest tidal flows in the world. Various projects are underway to harness this endless energy source, and the whisky distilleries on the island, all situated within a stone’s throw of the sea, are working together to make use of this local power source. Power from tides is fully renewable, zero carbon, and it provides very low cost energy after capital costs are paid off. Currently the distillers ship oil or gas to the island to make their spirit, this is both cost and carbon inefficient, so the developers of low carbon power projects have a ready market.

Low carbon power generation doesn’t just come from tidal flows in sea water. Latent heat in water can be stepped up using heat pumps to heat thermal stores. Companies such as Star Renewables of Glasgow produce well established examples of heat pump technology. Heat pumps can take water from boreholes and rivers. Indeed power can be dumped into hot wells by a blend of whatever green energy is most suitable; for example the Western Isles have some of the best performing wind turbines in Europe, our practice is currently working on projects which use direct line connections to wind-generated electricity, converting power to heat in different ways which is used for spirit making.

Will it change the character of the spirit?

The replacement of steam distilling is a huge hurdle for established distillers who understandably resist any change which could impact upon the established and closely-guarded character of the spirit.

This is a proposed change to the heat source, but not the method of distilling. It will not have a material effect upon the character of the spirit.

We shouldn’t forget that distillers have dramatically changed their methods of distilling before: In the 70’s direct fired stills were replaced by pot stills which were heated using internal steam coils. Until this point the direct heat had such an effect on the spirit that a rummager was needed to prevent the burning of solids in the gloopy base of a pot still. The changeover to steam heating removed this concentrated heat and the character of the spirit was changed significantly. This new heating method added efficiency; pressing a button to fire up a steam boiler was easier, cleaner and cheaper than the previous method of heating. Pot stills could be made of thinner copper. The atmosphere within the distillery was cleaner, not surprisingly steam coils were quickly taken up by the industry.

So spirit producers should not fear this change, more significant revolutions have been made to production in the past and sales have not been impacted. On the contrary branding and marketing experts must debate at what point consumers will be alienated by making no change and sticking with existing fossil fuel production.

The coming diversity of fuel sources will have less impact on the spirit than the change from direct firing to steam coils. There will be no one-size fits all solution to heating any more. We are at the start of the next industrial revolution in distilling. Production will be individual to each distillery, the green energy source can become another aspect of the story of a characterful single malt. Picture the future Islay distillers who tell of their wave powered whisky! Blended malts which have no link to a specific place will not have this environmental advantage, they will not be able to leverage the benefits of location in the same way.

Here is a unique opportunity for the nimble new wave of distillers. With no established flavour profile or spirit character at risk they can start afresh with green and efficient plants. Their energy, like their product, will be totally linked to their location.