Biogas technology implementation in treating tofu wastewater industries is one of the low carbon technologies that can be used in GHG emission reduction. The emission reduction from this action could be calculated from 2 sources. Firstly, the tofu industry wastewater which could emit CH4, NO2, and CO2 if there is no treatment applied. It also will pollute the environment and cause the decreasing in water quality which plays significant role for human health there. Tofu wastewater treatment could prevent emission because the organic wastewater is treated into biogas which can be used for fuel substitution in people’s daily activities. Secondly, as mentioned before, this activity could produce biogas that can be used in fossil fuel substitution; so, this fuel substitution also could be considered as mitigation action.
Taking these sources of reduction into consideration, to calculate the emission reduction in tofu wastewater treatment activities comprehensively, it is needed to measure the reduction in energy sector and wastewater sector.
There are methodologies that could be used in the calculation, for instance IPCC guidelines, CDM project calculation, and other relevant methods. Basically the available methods have similarities or even the same except for the ways they are used. For MRV system in Indonesia, although the official institutions and system has not yet established yet, there are several methodologies use in different ways, for example the IPCC guidelines is used in RAN/RAD GRK, while Nusantara Carbon Scheme as Indonesia’s voluntary carbon market uses ISO 14064 series. In the other hand, there are also regional carbon markets such as EU-ETS and J-VETS that also use different methods. If Indonesia is willing to join these regional carbon market, Indonesia has to prepare itself to know about the system involved in them, but CDM approach might be appropriate to be used as standard in the calculation.
Considering the RAD GRK for Central Java province as mentioned in previous workshop has decided to include the biogas technology implementation in tofu wastewater treatment to be one of the actions in their mitigation plans, here, we focused on IPCC 2006 guideline which is used as official method. However, we could also use the CDM methodologies namely AM0013 and AMS-H for detailed calculation in estimating the emission reduction. It is possible in the future that not only Central Java province who has planned to use the biogas from tofu waste but also the other regions in different policy, or other mechanisms that possible to dig the potencies of this technology.