Several of our previous blogs have touched on some of the high points of biomass handling and feedstock storage. We have discussed the importance of managing feedstock moisture and keyed into some of the pros and cons of round bales, square bales, and forage harvested material. But having a high level knowledge of biomass inventory and storage just scratches the surface. A truly effective inventory and storage systems is an optimized, integrated system that is unique to each feedstock and project.
Genera Energy has performed extensive research evaluating a variety of storage methods that determine dry matter loss as well as the subsequent changes in chemical composition of stored biomass. By handling tens of thousands of tons of material, we also have a comprehensive understanding of storage costs. When the costs of high quality tarps, a well-draining storage site, labor, equipment, and tarp maintenance are accounted for, it is clear that these costs can be quite substantial and are not to be overlooked. These costs are significant enough that other storage alternatives begin to look quite appealing as viable alternatives. So if we employ a cheaper and less effective storage scenario, is there a level of increased dry matter loss that can be tolerated if it off sets some of the storage costs? What is the cost-benefit analysis? And if a particular level of dry matter loss can be expected and built into the full cost of feedstock, what is that breakeven point? As with any operation, it is easy to get sucked into the thinking of “This is how we have always done it!” Tarping is typically the gold standard for biomass storage but Genera Energy is pushing the envelope to fully evaluate the effectiveness and the economics of a variety of other harvest, storage, and delivery scenarios.
By understanding that there is a cost to losing dry matter due to biological degradation as well as the cost to store, Genera Energy has performed some very detailed economic analyses to optimize harvest and storage operations. By incorporating a mix of just in time delivery and first in, first out inventory scheduling, as well as some lower cost storage methods (think bales stored out in the open with no use of tarps), Genera Energy has determined the lowest cost delivery and storage scenario for a variety of feedstocks. The key is knowing the threshold of dry matter loss and compositional changes due to open storage versus the cost of traditional storage methods.
In addition to optimally scheduling the movement and storage of bales, we have also performed research evaluating some more “outside of the box” storage methods. Genera Energy has done a full study of the performance of an innovative type of bale wrap produced by John Deere known as “B-Wrap”. This wrap allows internal moisture to vent out of the bale while also keeping precipitation from entering into the bale, therefore offering a potential tool that could remove tarping operations. We compared B-Wrap to traditionally stored net wrapped round bales to evaluate the effectiveness of each storage scenario. For our most recent storage research, Genera has partnered with Idaho National Lab to evaluate the viability of chopped switchgrass stored in open piles. Forage harvested feedstocks are expected to play a very important role in the biomass supply chain so it is crucial that we have a full understanding of handling and storing bulk material. We sought to mimic the structure of a stacker reclaim pile that is commonly used in the wood chip and coal industries and constructed three large piles of switchgrass: one field chopped, one tub ground, and one tub ground covered with tarps. To measure the success or failure of storing in these piles, we are measuring dry matter loss, chemical composition, and actively measuring temperature within the piles to gauge any biological heating due to decomposition. This study is still ongoing but we are seeing some very promising results!
Check back in regulary as Genera Energy continues to identify leading edge storage solutions that combine effectiveness with cost reduction. Call today to learn how our solutions can improve your supply chain by reducing risk and cost!
Lance Stewart, Supply Chain Manager
