The ECOBUS project increases environmental protection and the quality of life of citizens in Valencia. The procedure for the collection of used vegetable oil will prevent it from being dumped into the public drainage system, helping to reduce the rodent population in the sewage system and also reduce the jellyfish population in local sea water. On the other hand, biodiesel fuel used in the ECOBUS project reduces the emission of atmospheric contaminants from EMT urban bus exhausts.

A system of collecting used vegetable oil from the catering and restaurant trade and the food services industry by areas, covering the entire city of Valencia. These oils are then processed and undergo a chemical treatment at a transformation plant for the purpose of producing biodieself fuel to be used by urban buses.

 

Milestones
   
 
 
 		 COLLECTION PROCEDURE

The collection procedure involves oils used in the frying process in bars, restaurants and hotels, where the generation of this vegetable fat is widely extended and highly localised.

All collaborating establishments are identified with a sticker, and they are given containers for the collection of used oil. Subsequently the oil collected in this way is processed in a plant that transforms it into biodiesel fuel, which is then used in Valencia’s EMT urban bus fleet.

ENGINE TEST

Specific tests are made using the biodiesel fuel in engines under controlled operating conditions. The aim of these tests is to obtain data on the effects of different mixtures of biodiesel fuel as with respect to polluting emissions and engine performance, as well as engine durability.

The main variables to be measured are engine par, fuel consumption, polluting emissions (NOx, smoke opacity, CO, HC, CO2) among others. The tests start with stable engine conditions for subsequent simulation of transit operating cycles.

OPERATION IN URBAN BUSES

Over the two-year span of this project it is estimated that the volume of used vegetable oil collected for conversion into biodiesel fuel will be sufficient to supply 25% of the requirements of the entire fleet of EMT city buses in Valencia, in a proportion of diesel/biodiesel fuel mix from 5 to 30%, equivalent to a total of 120 buses.

The buses chosen for this purpose undergo a preliminary test to evaluate their initial conditions and their suitability for this project. To keep track of the results of this test a strict control is made of engine emissions and performance for each bus engine by means of regular inspections.

The parameters investigated are emissions of CO, CO2, HG, NOx and smoke, engine par, fuel consumption and oil consumption. In addition, a detailed register is drawn up of any occurrences during service, for the purpose of establishing clear-cut relationships between the effects of the new biofuel and vehicle reliability.

Also evaluated are another three basic aspects:
  • Environmental effects
  • Operating costs
  • Service reliability.


The final step of the project is to study the feasibility of this pilot experience and its possible application in other Spanish and European cities, especially those with eating habits similar to those of the Mediterranean diet, where large amounts of vegetable oil are used.

ENVIRONMENTAL BENEFITS OF BIODIESEL FUEL

  • Prevents public health problems, as it keeps used oil from being used for the manufacture of animal food.
  • Provides energy savings in municipal sewage treatment plants, due to the reduction in the volume of waste oil products.
  • Offers a decrease in nutrients in waste waters, thereby reducing the cost of rat control in the municipal drain system, as well as the number of jellyfish in coastal waters.
  • Increases the city’s environmental protection, enhances conservation of vegetation, historic monuments and facades, because biodiesel fuel reduces the emission of conventional fuel pollutants.
  • Maintains performance in bus engines, which need no modification for use, ensuring sustainable transport in the city.
  • Is fully in line with European strategies for promoting biofuels and diversifying energy sources.
  • Presents various operative advantages, as it is non-hazardous and biodegradable.
  • Contributes to the sustainable development of the city of Valencia.