We got the idea after living in France and Italy where pellets are sold in supermarkets. We loved it, but we wanted something more sustainable. Grow hemp locally and pelletize the inner core (hurd). Replace the wood pellets and use it to heat our home.
Compared to wood, the trees that takes years to grow and actively store carbon, this could be a good idea to save the forest. Hemp can fully grow to 3-4 meters in just 100 days!
In energy policy terms, wood is one form of solid biomass, which also includes agricultural crops and residues, herbaceous and energy crops, and organic waste, such as food waste or manure. Biomass-based energy is the oldest source of consumer energy known to humans and is still the largest source of renewable energy worldwide, accounted for an estimated 8.9 per cent of world total primary energy supply in 2014. (1)
In the UK, wood pellet consumption in 2018 was 8,5 MILLION tons. (2) Most is imported, without much knowledge if they are sustainably made or from perfectly healthy forest that would be better left standing and storing CO2. We want to replace some of this import with locally grown hemp, converted into pellets and processed for similar or better energy value. This is bold and this might be far off reality. Hemp pellets we tested initally are only half of (FixC carbon) that wood shavings give, let alone EN+ wood pellets.
Therefore, we want the Lighter Leaf project to succeed. We need to conserve the healthy forests. By growing hemp, we can capture much more Co2 and store in the ground left with the roots, and in the fibers whom we use to make the strongest natural material we have known for thousands of years.
We do not claim to be carbon neutral, we are burning carbon with our product. We do not want to replace wood pellets that are made from maintaining older, biodiverse forests, processed sustainably. They draw down carbon levels and help buffer imperiled ecosystems against the impacts of climate change. We want to save the healthy round trees, cut down by greed, at the cost of the environment. We want to grow locally, everywhere, and minimize the carbon footprint on shipping too.
Every tonne of industrial hemp stems contains almost half a tonne of Carbon absorbed from the atmosphere (44.46% of stem dry weight). Converting Carbon to CO2 (12T of C equals 44T of CO2(IPCC)), that represents 1.63 tonnes of CO2 absorption per tonne of UK Hemp stem harvested. For the purposes estimation, we use an average figure of 10T/ha of CO2 absorption. The roots and leaf mulch (not including the hard to measure fibrous root material) left in situ represents 20% of the mass of the harvested material. The resulting Carbon content absorbed but remaining in the soil, will therefore be approximately 0.084 tonnes per tonne of harvested material. (42% w/w) Yield estimates are (5.5 – 8 T/ha) this represents 0.46 to 0.67 tonnes of Carbon per hectare (based on UK statistics) absorbed but left in situ after Hemp cultivation. That represents 1.67 to 2.46 T/ha of CO2 absorbed but left in situ per hectare of UK Hemp Cultivation. (3)
For our production plans we visited Easypack Automation, Pelleting, and packing machinery specialists located in Horsham, West Sussex. They run an impressive full factory pelletizing line, pressing anything from Miscanthus grass to wood and food for animals. For a full industrial line, they have the plant and can manufacture and set it up for you in just few months.
We needed a smaller scale setup for our testing and trials. After turning to Sizer Engineering, Rotherham, South Yorkshire, we sent them our first hemp hurd to press. The pellets came back and you can just imagine the moment when we opened the boxes.
There are many varieties of hemp. We need to find the right strain for our latitude, with the correct amount of energy. We are not just interesting in the burn, far from it. We want to capture the syngas from the process, filter it and produce hydrogen too.
We will continue to test our material to use as a substitute for imported wood, and we are testing our pellets at a University in Germany to use in a professional build gasifier, for heating and producing enought electricity for your home and even deposit the excess to the grid.
The Lighter Leaf project