Pre-feasibility study of a waste wood district cogeneration in Sambuca industrial park as an area resources recovery project in the middle of Chianti hills, Italy
Type: CaseStudy
Case Study (447 KB PDF)Summary
The aim of this study is to identify an optimal and profitable solution that could take advantage of waste wood resources in Sambuca industrial park. The study has suggested different possibilities of biomass energetic use but the analysis key elements have shown that a small-scale gasifier installation and production of electric and thermal energy with a CHP internal combustion engine is the most profitable solution. Many environmental benefits could arise (1320 tCO2/y avoided and 554 TOE/y avoided) and the initiative, being one of the few Italian examples of local recovery of wood wastes for small cogeneration, could represent a valuable starting point. There is also the opportunity of combine CHP plant with wastewater treatment facilities, which allowed interesting technical developments and efficiency improvements.
Keywords: feasibility study, recovery of residues, combined heat and power generation (CHP)
Results
The size and the technical characteristics of this plant have been identified through the evaluation of data on the amount of wood resource continuously available during the year.
Technical characteristics of the plant:
| Operating hours | 7.500 h/y |
| Electric Power | 233 kWe |
| Gasifier Thermal Power | 1.165 kWth |
| Electrical Energy Efficiency | 20% |
| Thermal Energy Efficiency | 36% |
| Heat of cogeneration | 419 kWth |
| Electricity production | 1.747.000 kWhe/y |
| Maximum heat amount | 3.144.500 kWhth/y |
| Biomass Low Heating Value (LHV) | 14.114 kJ/kg |
| Biomass mass flow rate | 300 kg/h |
| Investment initial cost | 720.400 € |
| Annual O&M cost | 93.500 €/y |
| Annual benefit (case A) | 208.400 €/y |
| Annual benefits (case B) | 242.005 €/y |
| Income tax rate | 40% |
| Project life | 15 years |
| Discounted rate | 12,0% |
| Inflation | 2,5% |
| Average wood biomass cost (transport) | 10 € /t |
| Avoided cost of users thermal energy | 0,052 € /kWh |
For the plant there are very profitable scenarios:
|
Case A
|
Case A
|
Case B
|
Case B
|
|
| Self financed Investment % |
100%
|
75%
|
100%
|
75%
|
| Tuscany State incentive % |
-
|
25%
|
-
|
25%
|
| NPV |
€211.210
|
€391.300
|
€371.120
|
€551.200
|
| IRR |
17,87%
|
25,88%
|
21,77%
|
30,57%
|
| Profitability Index - PI |
1,29
|
1,72
|
1,52
|
2,02
|
| Simple Payback Time |
3,5 years
|
2,6 years
|
3,0 years
|
2,2 years
|
| Discounted Payback Time |
7-8 years
|
4-5 years
|
6-7 years
|
4-5 years
|
Contacts
Italy
-
Agenzia Fiorentina per l'Energia Srl
Florence Energy Agency Ltd
