Biomass energy potential analysis ENERBUILD
This energy potential analysis was conducted within the ENERBUILD project. An article about the biomass energy potential analysis has been published in the publication Producing energy on buildings in the Alpine Space - synthesis.
Description and synthesis of the work
Aim of the work was to investigate on biomass utilization and potential in Social Housing. This task was led together with the social housing agency of the province of Turin ATC (Agenzia Territoriale casa) which gave a list of 5.230 addresses corresponding to 31.388 apartments, among which:
- 18.705 apartments are owned directly by ATC and the rest is owned by other subjects, as municipalities or public bodies.
- 18.803 apartments are situated in the municipality of Torino, where major investigation about the feasibility of a biomass plant must be done, particularly related to flue gas emissions.
- 2.358 buildings, that are 12.585 apartments, are situated in an extra urban area, where constraints for biomass utilization are less strong.
These buildings were built between 1900 and 2011.
Data about installed plants are available for only 751 addresses and energy consumptions are available for only 270 of them. At present, it is not clear if the motivation for the difference in the number of apartments and records managed by ATC and the ones of which the energy consumption is available. The total annual expense for energy is reported at 12.600.000 Euro.
150 addresses (the related number of apartments is not clear), equivalent to 1.000.000 heated mc are located outside the municipality of Torino, and the related annual energy expense is 5.900.000 Euro/y. The price for heated volume varies from 4 to 11 Euro/mc y (and a strange 21 Euro/mc y in Pinerolo); the average price is 6,1 Euro/mc year. With an estimated cost of 0,85 Euro/Nmc of natural gas, the total gas consumption is around 6.000.000 mc, and this corresponds to 53.530 MWh. The estimated consumption for heated surface (hypothesis of an internal height of apartments of 3m) varies from 350 to 110 kWh/mq year (with a strange 40 kWh/mq year in Volvera); the simple average is 190 kWh/mq year.
In the theoretical case of complete utilization of biomass for these apartments, using biomass from forestry management, with 50% of humidity and a heating value of 2.200 kWh/t, the total annual use is 28.000 t. If the cost of biomass is 65Euro/t, the total expense for annual heating of the entire volume will be 1.800.000 Euro, that means 3.900.000 Euro of savings that can be used for dealing with the investment cost of the biomass systems.
This analysis shows a huge potential for biomass application in the Province of Torino than will be further investigated.
All buildings with available data were analyzed, depending on their actual energy system (Natural Gas, Heating Oil, District Heating).
The total energy consumption and the specific energy requirement are analyzed in the plot. The specific values seem to be in a specific range, with some differences probably due to geo-graphic distribution of the apartments, building qualities and difference of operation times.
The main goal was to assess the total actual energy consumption and the potential reduction of CO2 emissions. The global results are shown in the two graphs on the left side.
The cost savings are strictly related to the energy consumption, while CO2 emissions are slightly different because of the lower emission factor associated with district heating.
The substitution of heating oil and natural gas fueled systems appears more convenient than district heating because of a larger decrease of emissions and other aspects linked to infra-structure, components substitutions and system maintenance.
Hence only oil and natural gas fueled system were analyzed to assess the potential energy and emission savings associated with the conversion to biomass systems. Using a cost of 60 Euro/ton for biomass from forestry management and a heating value of 2,2 kWh/kg, the annual consumption of biomass is about 52.000 t/y for the selected systems. The corresponding CO2 emissions reduction is about 25.000 t/y. The action will be focused firstly on buildings with high specific and total consumption, resulting in major energy savings.
The third graph on the left shows the comparison of the actual situation and the planned scenario with respect to annual cost and heated volume. A linear interpolation on available data provide a price decrease from 5,2 Euro/m3 to 1,8 Euro/m3 switching to biomass fueled systems (not considering investment and maintenance costs).
Further information and contact
via Lagrange 24
Resp. P. O: "Riqualificazione Urbana Sotenibile"
+39 011 432 3807
DENER-Department for Energy, Politecnico die Torino
Luca Degiorgis, PhD
C.so Duca degli Abruzzi 24
+39 011 4529