RENEWABLE ENERGY ON THE ISLE OF MULL
We quite naturally have to, in many ways, be resourceful living on Mull, and that has been the case since the beginning. Doing, making and producing things ourselves has always been a vital part of how we've managed to build a forward-thinking, sustainable home here on Mull for the generations to come.
One huge source of energy we all tend to forget is of course the sun. A resource that all farmers use and take for granted. All the plants need it to soak up all the carbon, to create new life. It is the start of the natural cycle of life that we all enjoy and should be looked after.
Scotland also enjoys its fair share of Wind and Rain. We started building our water turbine back in the early 1990’s. We had the land surveyed and got a few quotes. For such a small scale installation it was not feasible to have other companies install it for us. Over the years of building the farm we had become experienced in constructing things and building a power station ourselves was exciting – a little daunting as well truth be told.
We had purchased excavators to build the site for the farm I think we were on our third as they were always worn out. The site was surveyed, and we started … The first electricity was generated about 15 years later in 2010! Part of the project turned some wet ground into a pond in which we have Brown Trout, Herons, and the occasional Otter.
During the year, we both import and export electricity. It powers the Farm, the distillery and Island Bakery Organics together with a few houses. In balance we export around 50% more than we use which is great and we are proud of.
We also have a small wind turbine and in the future hope to have solar panels to produce a little electricity. We must not forget though that the fields themselves transform carbon into grass with the aid of the Sun.
When we first moved to Sgriob-ruadh we pasteurised the milk for liquid sales to the islands. The only way we could do this was with electricity. During the winter the milk was turned into cheese. Back then it was only quite small quantities and the cheese was heated with a water heater from a shower. After a short while we needed a larger cheese vat and it needed more heat. We had to use a diesel burner. It was old and frequently broke down.
By 1999 all the equipment for producing cartons of pasteurised milk was also worn out so we decided to concentrate on cheese. A new dairy was built with a bigger cheese vat.
We needed more heat even faster now. A new diesel boiler was very expensive, and the forestry commission was growing trees all around us. A log burner was found for the job but it could not produce heat fast enough but plenty over the day.
A large milk tank from Islay dairy was installed as a hot water tank and a swimming pool for warm water. To make it work a large heat exchanger which was also commissioned.
The evening milk is cooled down for storage overnight. The heat energy that is removed is stored in our thermal battery (swimming pool). In the morning the milk it heated back up and mixed with the morning milking in the cheese vat. The majority of the heat for this comes from the swimming pool and then the temperature is increased slightly with the hot water. The cheesemaking process needs a bit more heat and this comes from the high temperature thermal battery (Hot water tank) All the time the little log burner was gently doing what it did slowly.
The logs that we used for the log burner arrived 3m long and log burner was around 1.4m deep. So we cut the logs twice to make “small” logs about 1m long.
Over the years we wore out 2 log burners and to be honest we wore ourselves out as well.
Possibly around 2007 the idea of fermenting the whey was lodged in my fathers brain by a microbiologist. It just sort of stayed there for a few years, stuck.
By 2017 loading the log burner had become a real chore the logs from the forestry were getting larger and sometimes it would take 2 people to throw the meter long 30cm diameter logs in. Now and again they would be cut down but that made it difficult to get enough wood in.
We had been avoiding going down the chipping route as that used fossil fuels but the wood burns more efficiently and our backs were sore. The idea of fermenting and distilling the whey also resurfaced and this of course needs more heat. So we installed the wood chip boiler in a new shed that was going to be large enough to power everything.
Over the next few years plans were made to build the distillery over the top of the new wood chip boiler.
At the start of 2019 the builders arrived and the Stills were being built in Germany. After putting the frame up, Covid happened.
We had to carry on producing food but in our spare time the building was completed. The Stills arrived in 2020 but we could find no engineers to install all the equipment. Over the years we have developed many skills not least of which is stainless steel pipe welding and fabrication.
So now the wood chip boiler (Biomass Boiler) provides all the heat to ferment and distil all the whey from the cheese production. It runs at high temperatures and a lot of energy is wasted from most distilleries. We however have re-piped the farm and now all that surplus heat goes to making the cheese!
We've built a self-sustaining 'circular economy' on Sgriob-Ruadh Farm, and these 8 factors allow us to run sustainably and cut wastage down to the absolute minimum.
Breeding our dairy herd.
Use milk only from our own cows.
Create and mature our cheese, all at Sgriob-ruadh
Curds for cheese making, whey for distilling, spent whey for feeding.
The farm is powered by 100% renewable energy - all generated on site.
Woodchip, wind and water producing our energy.
Committed to creating.
Heat Storage System
The fresh morning milk is runs directly to the cheese vat by gravity and maintains its temperature, but the evening milk which needs to be stored overnight, must be first be cooled. We transfer heat from this milk into a "thermal battery", which takes the form of a swimming pool. The cooled milk must then be warmed up again for cheesemaking, and we return the heat stored in the pool to do this, creating the perfect cosy environment for the cheese bacteria to create the cheese.
Shortly after moving to Mull, we began preparations to utilise hydro-electric energy — creating a 'hydro pond' to collect water in the first instance. At that time, no payment systems for the surplus energy was in place. Installing the equipment was too expensive.
Many years on, a new 'FITs' (Feed-In Tariff Scheme) was introduced by the government — allowing us to complete the project.
We now have a 180kW hydro electric scheme that uses water from a nearby river through our pond and turbine, before re-joining the river a little further downstream.
The electricity is used all over the farm and also at the Island Bakery to make biscuits, with the surplus fed into the national grid.
The header pond for the Hydro has created a wonderful home for Otters, Herons and Trout.
Sgriob-ruadh Farm also has a 65kW wind turbine that stands on a hill above the farm making the most of the wild west coast wind that blows across our shores.
Sustainable Wood Chip Boiler
Making cheese and alcohol from the milk requires quite a lot of warmth, year round, both for for the cheesemaking bacteria and alcohol producing yeast. There is much farmed forestry on Mull, providing us the wood which we chip for fuel.
Our cheese vat was one of the first in the UK to be converted from diesel or electric to Biomass and now the distillery is one of a very few to be also powered by wood.
100% of the farm's electricity and heating is produced on-site through renewable energy
Re-use, Re-cycle and Re-purpose
The Reades are a family of doers, thinkers and tinkerers, and a lot of our equipment has been designed and constructed by ourselves.
Where possible, we will always re-use materials, produce and equipment. We won't throw away anything of use and value — one great example of this is our Glass Barn, which was built using re-cycled materials from an old village hall.
Living on an island for over 40 years, we have become a family of very independent and capable people. We have a lot of mechanical equipment on the farm — from tractors, to cheese making kit, to renewable energy infrastructure.
If something breaks down, we need to be able to fix it, replace it with a back-up or construct a new one from old equipment. This is the self-sufficient family ethos that keeps things moving on Sgriob-Ruadh Farm.