**Table 3.**

*Number of confined heads, semi-confined heads, total heads and slaughtered heads, and energy demand (MWh) for the baseline scenario and scenario 1, in Brazil, in 2000, 2005, 2010, 2015, 2020, 2025 and 2030.*

## *Biogas Generation from Bovine Confinement: An Energy Policy Option for Brazil DOI: http://dx.doi.org/10.5772/intechopen.99828*

### **Figure 4.**

*Rate of number of confined cattle on total cattle with some type of confinement and number of semi-confined cattle on total cattle with some confinement in Brazil, % (2000–2015). Source: Prepared by the authors.*

For semi-confined cattle, this average rate was 40.6%. Therefore, the number of confined cattle will rise from a little over four million in 2015 to around 15.9 million in 2030. Semi-confined cattle will increase from almost 2.7 million (2015) to almost 10.9 million. Total cattle with some type of confinement in 2030 will be around 26.8 million, representing an increase of 74.2% in relation to 2015.

## **4.4 Scenario 3: increases in the rate of cattle with some form of confinement and the time of confinement**

Joining scenarios 1 and 2 creates scenario 3, thus, as has been seen in the previous scenarios, only the basic values for the calculation of the creation of biogas and emissions are altered. Permitted in this scenario is the analysis of all the proposed possibilities for the intensification of livestock raising through the confinement of cattle, and through the increase in both confinement time and the total rate of cattle in some form of confinement.

After the analysis of each of the proposed scenarios and how the basic variables are modified in the three scenarios, the biogas generation potential and to what extent this can meet the demand for energy of slaughterhouses and abattoirs, and the agricultural sector, is examined, as well as the impact on emissions of the insertion of biogas in the energy matrix. In short, it shows how cattle confinement can contribute to energy policy as a complementary renewable source capable of guaranteeing energy security from the point of view of supply without harming the environment.

### **5. Results**

There is a high potential for the use of biogas. Even without any intensification policy it will be possible to meet almost 80% of the energy demands of abattoirs and slaughterhouses in 2015. In 2030, not only will it be possible to meet all energy demands necessary for animal slaughterhouses, but also energy can be offered to the Brazilian electricity system with an addition of around 371.1 GW/h year. In the case of the agricultural sector, first, it is estimated that the demand for electricity of slaughterhouses and abattoirs will represent almost 6% of the total electricity consumed by the sector in 2015. By 2030 it is estimated that this value will be approximately 4%. The insertion of biogas as a source of electricity can be noted that renewable resources

### *Biogas Generation from Bovine Confinement: An Energy Policy Option for Brazil DOI: http://dx.doi.org/10.5772/intechopen.99828*

can meet approximately 14.9% of the electricity demands of the agricultural sector in 2030, in a scenario with both an increase in the confinement rate and an expansion of time spent in confinement (Scenario 3). The importance of the use of biogas as an alternative energy source is so relevant that without any alteration in the country's beef productive system in 2015 biogas could generate sufficient electricity to meet about 4.8% of the demands of the agricultural sector, and in 2030 this value would be practically the same, a little more than 4.7% (**Figure 5**). Changes in confinement time or in the confinement rate can increase the offer of biogas and can increase even more the additional offer to the grid with an addition of almost 1402.4 GW/h (scenario 1), 2867.1 GW/h (scenario 2), or 5146.3 GW/h (scenario 3). As **Figure 6** shows, it is possible to create more than three times the energy demand necessary for animal slaughter (offer of biogas/energy demand = 378.6%) in 2030.

It can be noted that increased confinement time (scenario 1) creates a lower increase in the offer of biogas for electric energy when compared to the increase

### **Figure 5.**

*Relation between the supply of biogas and electricity demand for agricultural sector, for each scenario, % (2015, 2010, 2025 and 2030). Source: Prepared by the authors.*

### **Figure 6.**

*Relation between the supply of biogas and the electricity demand for slaughterhouses, % (2015, 2020, 2025 and 2030). Source: Prepared by the authors.*

**Figure 7.**

*Emission reduction with biogas use, for each scenario, in GgCO2e (2015, 2020, 2025 and 2030). Source: Prepared by the authors.*

in the confinement rate and, above all, that the sum of the different intensification polices results in a significant increase. Thus, this result shows the strategic importance of biogas in Brazil as an energy source capable not only of meeting the demand of slaughterhouses and abattoirs, but also part of the energy demands of the agricultural sector.

An additional positive effect of the use of biogas, in addition to the expansion of energy demands, is on the reduction of GHG emissions. Despite having a low grid emission factor due to the high share of hydroelectricity in the Brazilian energetic matrix, the insertion of a renewable source with the low GHG emissions helps keep the emissions of the Brazilian electricity sector low. In the scenario with the implementation of all intensification policies in the agricultural sector (Scenario 3), it is possible to reduce in the long term (2030) a little more than 1201.56 GgCO2e. Without any policy, this reduction will reach 381.12 GgCO2e, as **Figure 7** shows.

### **6. Conclusion**

Despite being one of the largest beef producers in the world, Brazil still has low productivity indices in the livestock sector, in which the predominance of extensive system means that the country has a stocking rate of between 1 and 2 heads of cattle per hectare. Given this fact, the country has great potential to intensify the sector with the possibility of the reduction of the demand for electricity in abattoirs and slaughterhouses using biogas and even the agricultural sector as a whole and to reduce somewhat greenhouse gas emissions generated by the sector through the introduction of a new renewable and cleaner energy source.

In the scenarios analyzed, it was perceived that the use of biogas in beef cattle confinement is an interesting complementary energy policy, which fits into the need to diversify renewable energy sources to reduce potential problems in electricity supply, in relation to an energy matrix that is dependent on hydroelectricity to

### *Biogas Generation from Bovine Confinement: An Energy Policy Option for Brazil DOI: http://dx.doi.org/10.5772/intechopen.99828*

meet the growing demand of the agricultural sector for electricity. In scenario 3, it can be observed that the application of policies to intensify the livestock sector allows a considerable reduction in GHG emissions and to meet the needs of both the agricultural sector and the totality of the energy demand of slaughterhouses and abattoirs, which are close to the herd, facilitating the use of biogas to supply them.

More profound studies, assessing the economic question, such as the costs of expanded confinement and if, from the economic point of view, intensification is attractive, need to carry out to confirm whether, from the technical point of view, increasing beef confinement is an interesting energy policy to increase the offer of electricity and to reinforce the energy security of Brazil. The scenarios show the need to modernize livestock raising through the better use of the waste and the effluents created during the slaughter process and to propose as a short and midterm energy policy.

Therefore, the conclusion is reached that the use of biogas is important to reduce greenhouse gas emissions, contribute to cleaner energy generation and reduce the energy dependence of the agricultural sector in Brazil. In the face of climate change, this energy resource can help the country to help meet the goals proposed under the Paris Agreement and attract foreign investment in view of the enormous potential to generate energy and reduce emissions.
