What differentiates BIO2CHP from the many other waste-to-energy solutions?
The main differentiating characteristic is the scale / size (<150kW electric), while also the ability to use untreated organic waste and the focus to agro-food industries. Up to date there are no efficient alternatives on the market in such scales which can deal with the waste disposal and - mainly electrical - energy needs of small and medium agro-food industries effectively.
Who uses the generated energy?
Our customers have the following options: (a) use the power for their own needs, (b) sell the power to the grid. Depending on the regulations and standards on each country, the customer is consulted to use the most profitable option.
What is the current level of development of the technology?
To date, we have developed a working prototype which has worked for several hundreds of hours, under real life conditions with 4 different types of biomass residue: grape seeds, olive kernels, peach kernels and almond shells. Currently, we are building the first pre-commercial pilot to be installed and demonstrated at the facilities of a winery in northern Greece.
What makes this more convenient than a digester?
Gasification involves the partial combustion of a feedstock, in conditions of restricted air, to produce a low calorific value gas fuel that includes hydrogen, carbon monoxide and methane. Additional inert components in the gas are carbon dioxide and nitrogen. A gasifier coupled to a gas engine combines high efficiency (around 25% electrical efficiency and an additional 50-60% thermal efficiency) with small sizes at the scale of 20-150 kWel and at low installation cost. In addition, since gasification is a thermal process, the output can be rapidly modified just through altering the fuel feed rate, and thus provides higher flexibility in response to the requested loads. On the other hand, digestion provides a lower electrical efficiency (around 18%), it is not efficient for lower than 250kWel installations, has a higher cost, and is restricted in terms of feedstock type and load changes.
What waste can be used?
Organic residues with moisture <50% can be directly fed to the gasifier. Ideal moisture content is 10-20%. In addition, the ash content of the fuel should be lower than 25% to avoid additional maintenance of the unit. Feedstocks that are usually applied include agricultural residues, food industries residues, woodchips, sewage sludge, etc.
Do the waste streams need to be pre-processed?
The gasifier has a limitation in moisture (<50%) and in particle size (<2 inches), thus, a limited pre-processing is necessary. Part of the thermal energy produced is used for feedstock drying as an integrated part of the feeding system of the unit. Additional already existing equipment (e.g. crusher) may be required depending on the state and type of the waste stream.
What are the potential applications?
Apart from residue suitability for our technology, the energy needs and the waste/residue disposal cost for the customer should also be considered. In addition, year-long energy needs and residue availability are also important factors in delivering the best value to the customer. Potential uses are in wineries, chicken processing factories, cotton industry, rice industry, paper industry, breweries, olive mills, wood processing and fruit processing (jams, juices, etc.).
What is the climate impact?
For every 20kWel unit we save approx. 62 tnCO2eq per year, equivalent to the electrification of 9 households.