Riccardo Piunti, president of CONOU, explains to Rinnovabili why using HVO made from waste oils is both cost-effective and sustainable.
Italy excels in many sectors, and one of them is the collection of used lubricating oils. The country has achieved an exceptional regeneration and circularity rate: 98%.
This success is largely due to CONOU, the National Consortium for Used Mineral Oils, which for over 40 years has been a leader not only in Italy but across Europe. The consortium has effectively “connected” various businesses, raising awareness and engaging them in this best practice. And as is often the case, one good initiative leads to another.
With the goal of pursuing an increasingly circular and sustainable model, CONOU has signed a memorandum of understanding with UNEM (Union for Energy and Mobility) to promote the use of HVO biodiesel (Hydrotreated Vegetable Oil), a biofuel made from used oils, in the 678 vehicles the consortium operates to collect waste oil from more than 103,000 collection points across the country.
At Rinnovabili, we visited CONOU’s headquarters to speak with its president, Riccardo Piunti, and understand how this low-emission biofuel stands as a viable alternative to traditional diesel.
President Piunti, let’s start with the basics. What is HVO biodiesel, and how is it produced?
Biofuels derived from vegetable oils or used cooking oils have been around for a long time. Years ago, while working at Eni, biodiesel was widely used due to tax incentives. However, in the 1990s, low-blend biodiesel mixed with conventional diesel caused several issues, including the formation of algae and mold in tanks due to its instability.
Later, Eni saw an opportunity to repurpose decommissioned refineries to produce biofuels from waste oils. The HVO we are discussing today is made from used frying oil and other vegetable oil waste but undergoes an advanced refining process that allows it to be used at 100% purity without technical issues. To achieve this, specific plants were built to chemically refine the raw material, making it fully compatible with diesel engines.
Hydrogenation, using hydrogen, is the key process for purifying biofuel. How does this process work?
The process requires a catalyst, the right temperature, and sufficient hydrogen pressure. Hydrogen plays a critical role in refining because it removes contaminants, ensuring a stable and clean final product. Although the process consumes energy, the overall balance remains positive since it produces high-quality diesel from waste materials.
What role has CONOU played in this transition?
CONOU’s founding members, including oil companies, regenerators, and collectors, have actively promoted HVO adoption, recognizing its significant environmental benefits. HVO biodiesel cuts CO₂ emissions by over 70% compared to traditional diesel, making it a crucial tool in reducing the carbon footprint of transportation.
Can HVO be used both blended with conventional diesel and in its pure form?
Yes, but pure HVO requires modern engines, like Euro 6 models. That’s why, in discussions with UNEM president Gianni Murano, we agreed to encourage collectors—who drive heavy-duty vehicles on highways and city roads—to adopt HVO.
CONOU itself is not a company but a network of independent businesses. We asked them to test HVO, and the first case was a major success. A large collector in northern Italy, who had already upgraded to Euro 6 trucks, initially used blended HVO and then switched to pure HVO, confirming its effectiveness.
How does HVO impact fuel consumption?
Our collectors observed that fuel consumption is slightly higher, about 5% more, compared to conventional diesel due to HVO’s lower density. However, when considering the full lifecycle, there’s no economic loss.The particulate filter (DPF), which burns fuel to eliminate residue buildup, activates half as often compared to diesel. Additionally, there are no sediment, algae, or mold issues in fuel tanks, which stay cleaner and require less maintenance.
What about costs compared to conventional diesel?
HVO is priced similarly to diesel and, in some cases, is even cheaper because it’s not affected by geopolitical factors. Moreover, CONOU has provided incentives to encourage its use. One particularly successful case involved a collector who started using HVO in June 2024 and had already consumed 146,000 liters by the end of the year.
Will there be enough raw material if HVO becomes widely adopted?
This is a critical issue. Eni has already converted refineries in Gela, Venice, and Livorno into bio-refineries. However, as HVO demand rises, used oil collection must also scale up. The household used oil recycling sector is still underdeveloped, but expanding it is a key challenge for the future.
What does the future hold for HVO biofuel in the next 10 years?
HVO and other alternative fuels will likely play a key role in heavy-duty, marine, and aviation transport. The challenge isn’t mechanical efficiency but availability and production volume. Meanwhile, the automotive industry has already embraced electrification, and aside from minor adjustments, that seems to be the direction it will continue to follow. However, biofuels remain a strong solution for decarbonizing industrial sectors and heavy transportation.
Is oil collection and HVO biodiesel production a uniquely Italian model?
The concept of vegetable-based diesel is very much an Italian innovation. We are leading in Europe, thanks to a long-standing culture of resourcefulness and waste reduction. Additionally, the consortium model has been a winning strategy. The industrial approach, Eni’s decision to repurpose existing refineries into recycling plants, was a particularly smart move.
