The person in charge of biofuel certifications and European projects of the Spanish Association for the Energy Valorization of Biomass (Avebiom) , Pablo Rodero, analyzes in this interview the evolution and progress of the biomass sector, as well as the energy valuation of by-products of the olive tree such as pomace, olive stone and pruning. In the case of olive pit, Rodero assures that much progress has been made and currently approximately 25-35% of production is cleaned and dried, being used in high-quality combustion devices.
How has the biomass sector evolved in recent years?
In recent years the biomass sector has made great strides in all aspects. The market for wood pellets has matured spectacularly in number of installations, quantities produced, etc. We have gone from practically 0 10 years ago to producing more than 700,000 tons of pellets in 2019 and installing more than 55,000 stoves annually, but the advance has been equally spectacular in technology at the level of efficiency, performance or emissions. It has nothing to do with a 10-year-old boiler that is currently being sold.
Also in other biomass such as olive pit, much progress has been made and currently approximately 25-35% of production is cleaned and dried and is used in high-quality combustion devices.
Perhaps the most important thing is the technological advance of boilers and stoves. Also the standardization of biofuels that little by little has been covering the most used domestic biofuels.
What advances would you highlight?
As I have commented previously, in combustion, both in boilers and stoves, much progress has been made in efficiency. Now the boilers are usually around 90-95% efficient and it is even higher with condensing boilers (over 103%) of some leading brands such as the Spanish Biocurve.
In the same sense, emissions have been progressively reduced at the same time that increasingly stringent regulations have emerged (ecodesign). Currently, particulate emissions and other emissions in ecodesign compliant boilers are really low when the fuel is of quality (certified) and properly maintained.
Another significant advance has been in the standardization of biofuels over the last 10-15 years and Avebiom has been very involved in this. If there is no standard - the European pellet standard dates from 2006 - we have made great progress thanks to European projects (Bionorm, Biomasud, Biomasud Plus) and currently most of the biomass for domestic use are standardized. This is the case of the most common and widespread biofuels (pellets, chips, briquettes or firewood in the ISO 17225 series of standards), but even some of a somewhat smaller scope - olive pit (UNE 164003) and nut shells (UNE 164004).
In addition, certifications with ENplus have been extended and cover an average of 70% of domestic pellets worldwide and over 83% in Spain. For other biofuels, BIOmasud is still not very widespread but continues to grow with good prospects for the future as administrations will increasingly tighten the requirements for biofuels.
"The olive stone, if it is valued, is a high quality biofuel"
There are several by-products of the olive tree that are susceptible to energy evaluation: pomace, olive pit and olive tree pruning. What is the production of each one?
Olive trees are neighboring trees so the annual production varies. An average production of the tree could give around 300,000-400,000 tons / year of olive pit; and about 800,000 tons / year of olive pomace.
These two biofuels tend to have very different destinations. The olive pomace is eminently industrial, for large boilers and is directed a lot to electricity generation. On the other hand, the olive stone, if it is valued, is a high quality biofuel, practically like the wood pellet, the problem is that only approximately one third is valued, the rest is sold as it leaves the oil mill and in large proportion to industrial customers. Although the trend is that it is increasingly valued due to the increasingly restrictive legislation. These fuels have a market and currently all the quantities produced are used. There would be room for growth in the olive pit market, since as I have mentioned, most of it is sold without added value, so if it is valued,
As for the pruning of the olive grove, the situation is practically the opposite, since approximately 10-15% of all production is used. Every two years all the olive trees are pruned and the thickest parts are used as firewood and the rest for industrial use (usually electricity generation). According to estimates, in Spain there would be 2,288,895 tons of dry matter / year (dry matter means that in green, as it is on the market, it has 20-30% humidity, so there would be more tons). Of these tons, as I mentioned before, only 10-15% is used, so the rest would be available.