The Renewable Energy Act of 2008 promotes the development, use and commercialization of renewable energy in the Philippines. The National Renewable Energy Board (NREB) was established by this Act and as such is responsible and empowered to formulate and recommend policies for the development of renewable energy sources.
General Overview on the Island of Panay
It is still one of the few provinces in the country that maintains a total of about 709 hectares of virgin forest. The province of Iloilo occupies the southern and northeastern part of the island of Panay. For one, not all rice produced in an area is milled in the same area.
This is because transportation and storage add significant additional costs to plant operations. The DOE has presented a sustainable low-carbon scenario for the coming years, as stated in the PEP Policy Strategies 2012-2030. There is an existing Department of Agriculture (DA) program to implement flat bed dryers e.g.
The basic principle of biomass rice dryers is the combustion of rice husks and the conversion of the produced heat to the paddy to reduce the moisture content. For the assessment of the combination of wood gasification and gas engine, assumptions have been made as stated in Table 5-1. Most of the rice mills contacted have already made some investments in rice dryers that work on rice husks.
Province of Aklan
Province of Antique
Province of Capiz
Province of Iloilo
Fuelwood
These facts explain why no significant amount of forest and wood residues are generated in Panay as no commercial wood processing operations exist. However, this wood production represents only a small part of the annual wood growth in forest plantations.
Charcoal
According to Table 2-2, an annual amount of nearly 18,000 tons of dry woody biomass from plantations will be available for energy purposes in Panay, concentrated in Antique and Iloilo.
Rice Husk Production
This can be a reliable means of estimating the theoretical amount of rice husks produced in the area, but in reality not all are available in the same area due to many factors affecting the processing process. Rice trading can significantly affect the amount of rice actually milled in an area compared to the amount produced in the same area. This value was used to calculate the equivalent energy potential of rice husks produced in the study area.
Lists of rice mills operating in the four provinces were obtained from the National Food Authority (NFA). The equivalent weight of a bag of rice husks varies from 7 to 10 kg depending on the moisture content.
Rice Straw
Although there are already a number of megawatt-scale utilization of rice husk for electricity and heat generation in Luzon, its utilization outside Luzon, such as in Panay, is still limited and mostly limited to small-scale fuel applications for cookstoves, furnaces, ovens, and dryers. either by direct combustion or by gasification. The use of rice husk for traditional and improved cooking stoves is the most widespread application in terms of the number of users, although the combined consumption is still insignificant because the usual consumption of these devices is very minimal in the range of 1 to 2 kilograms per hour only. Use for dryers comes in second in terms of unit numbers, but the combined consumption is greater than that for cookstoves.
Most of these dryers can dry an average of 120 bags of rice per batch, consuming an average of 30 bags of rice husk per batch. Using the ratio of 30 bags of rice husk to 120 bags of dried rice, the amount of rice husk consumed by 333 dryers per year is approximately 35,143.5 bags.
Coconut Residues
Based on these ratios and the total annual production, the amount of coconut scraps (shells and husks) produced per year is shown in Table 2-8. Sun drying – Place sliced walnuts, shelled or shelled, open side up to dry in the sun. Direct fire drying – cut walnuts, usually shelled, are placed face down on the slats of a smoke oven, which has a firebox without a chimney below (popularly called “tapahan”).
However, no data is available on the amount of copra that is dried using coconut waste. However, due to the rainy season, it is safe to assume that a significant amount of copra is being dried using this type of fuel.
Sugarcane Residues
According to the Philippine Coconut Authority (PCA), the typical composition of the whole coconut is as follows: meat 30%, water 22%, coir 12% and husk 35%. All but one of the millers interviewed use motorized roller mills to mechanically extract the cane juice. In the provinces of Capiz and Iloilo, most of the sugarcane produced is brought to large sugar mills where these are ground to produce raw and refined sugar.
Bagasse residues from these factories are used as fuel for the generation of heat and electricity to meet the energy needs of the factories. The national grid is operated by the National Grid Corporation of the Philippines (NGCP).
Electrical Energy Supply and Distribution
3 SPUG – Small Power Utilities Group, a group of NPC to electrify areas not connected to the main transmission network.
Energy Demand in the Households
Energy Demand in the Agricultural and Industry Sectors
Wood, metal and craft processes usually involve the use of power tools for welding, cutting, machining, grinding and drilling that draw power from the electricity grid or from diesel/petrol generator sets. Considering the current energy supply in Panay as well as the current mix in primary energy for power production, any further supply of renewable energy is necessary. The use of solid biomass for energy purposes usually includes several separated or coupled process steps.
It usually starts with one or more thermo-chemical conversion steps, including drying, pyrolysis gasification and combustion. This may involve simple heat transfer (e.g. for drying), the inclusion of one or more thermodynamic cycles (e.g. for power generation or cooling), or further uses (e.g. cells of fuel), depending on the first conversion steps.
Sustainable Wood Gasification and Gas Engine
This includes general information, a technical description, typical operating data (if available) and implementation examples (if available). the market). From here they are transported to the actual reformer, where the gasification process takes place. The product gas is cleaned of residual charcoal and ash using a filter before being fed to the gas engine.
Figure 4-2 shows a plant in Austria with a nominal output of 30 kWel, which has been in operation since 2010. The economics of small plants in the mentioned range of 30 to 45 kW are not so good compared to larger plants of up to 200-250 kW.
Sustainable Wood Pyrolysis for Charcoal Production
The investment costs of larger plants, however, are much higher (over PhP 50 million), and wood requirements would exceed the available regional supply. Furthermore, until charcoal is sold at a realistic market price and has to compete with illegal production, investment in improved wood production for charcoal/. Additional information can be obtained from the GIZ HERA project and from the Energypedia website https://energypedia.info/wiki/Charcoal_Production.
Sustainable Wood Pyrolysis plus Gas Engine
Rice Husk Combustion for Rice Drying
Figure 4-8 shows several circulating rice dryers at the National Food Authority (NFA) site in San José, Antique. The rice is dried and milled on site, with the final product to be stored in NFA's warehouse and sold in times of rice shortage.
Rice Husk Combustion and Water Steam Cycle
In steam-type steam turbines, steam can be extracted from the turbine at various stages. Before the cycle is closed, the steam must be condensed so that it can be pressurized again. An existing power station based on rice husk (Family Choice) was visited by consultants from the ForClim II project in March 2015 (see Figure 4-11 [13]).
The assumed cost in this study of PhP 1,000 per ton of rice hulls already takes into account the increased demand (rice hulls are now often simply dumped in vacant lots near rice mills). In this study, the steam cycle based on rice husks is recommended only for rice mills with sufficient in-house husk stock and significant energy consumption.
Rice Husk Combustion and Organic Rankine Cycle (ORC)
The assumptions to be made will be given and explained where necessary in the next section. Annual income is calculated as the sum of all monetary cash flows to the operator (including absolute earnings from the sale of electricity, purchase prices, sales of by-products, as well as additional earnings, e.g. due to lower rice losses during drying) and avoided consumption (e.g. electric energy from the grid, diesel fuel). The following assumptions apply to ecological calculations: reference carbon dioxide emissions from coal-fired power plants: 246.8 gCO2/MJel = 888.5 gCO2/MWhel [18].
In the Visayas, and especially in Panay, there is a large proportion of coal and oil-fired power plants. Considering the base load capability of biomass-fired power plants, it can be assumed that electric power from solid biomass will replace power from coal-fired power plants.
Sustainable Wood Gasification and Gas Engine
It should be noted that this assumption is only of a very general nature and does not correspond to calculation methods for funding through the Clean Development Mechanism (CDM). Average cost for purchasing electricity from the grid 11.7 PhP/KWh Avoided cost for purchasing electricity. PhP Annual carbon dioxide savings (compared to coal) 185 t . 1) FIT rate for biomass will be reduced by 0.5% every 2 years from January 2017, so the annual income will be slightly reduced after this date.
Sustainable Wood Pyrolysis for Charcoal Production
Sustainable Wood Pyrolysis plus Gas Engine
Rice Husk Combustion for Drying
Rice Husk Combustion + Water Steam Cycle
Rice husk combustion + Organic Rankine Cycle (ORC)
If all rice husks could be obtained for free (e.g. through cooperation between rice mills), energy production costs could be reduced to PhP 5.5554/kWh with an annual benefit of PhP 12.0 million. Sibalom municipality has already been identified as a potential site for a rice husk-fired cogeneration plant. The implementation of a small rice husk power plant (1-2 MWel) in Sibalom municipality should be supported by political and economic measures.
Private investors, especially rice mill owners, have invested and continue to invest in rice thresher rice dryers. However, the implementation of rice husk rice dryers is an interesting option for the Philippines, especially considering the potential reduction in rice grain losses during drying compared to traditional sun drying.
