Enormous quantities of straw in China are burnt in open fields or discarded randomly, leading to a serious waste of biomass resources and environmental pollution. To accelerate sustainable development, straw resources must be used efficiently and reduce carbon emissions. Based on a systematic literature review, this study summarizes China’s latest development in straw utilization. It analyzes the accounting methods, carbon emission reduction effects and potential of straw utilization. The study highlights that straw utilization in China can be categorized into five-dimensional straw utilization models (FDSUM). The cost of collection, storage and transportation, and straw utilization technology are the main factors affecting straw utilization. FDSUM contributes greatly to agricultural carbon reduction. Straw-to-fertilizer has the highest contribution, and straw-to-fuel has the largest carbon emission reduction potential. The carbon emission reduction from straw–to-fuel utilization in 2020 was 63.43 × 10⁹ kg CO₂. In addition, China has not developed a standardized carbon accounting method for straw utilization. China needs to prioritize straw-to-fertilizer and straw-to-fuel conversion and develop low-carbon production technologies. This study will serve as a reference to further improve the utilization of straw in China and provide preliminary ideas for establishing a unified national carbon accounting system for straw utilization.

The significance of this research is on maize, rice, sorghum, millet, groundnut, soybeans and cowpea straw for stronger sustainability in Ghana’s economic development. Quantifying and re-use of crop straw resources in Ghana is still at the infancy stage hampering the efficient recycling of these resources in a sustainable manner. Sustainability is straw as a renewable resource to improve soils, livestock production, generate renewable energy and reduce pollution for development. The aim of this research was to estimate the crop straw yield from 2006 to 2016 and identify the various utilization modes for major cereals and legumes in Ghana. In addition the distribution of maize, rice, sorghum and cowpea straw across major producing regions was calculated. Results obtained showed that 77,404,709.75 tonnes of cereals and legumes straw were produced in Ghana from 2006 to 2016. Cereal straw recorded a 72.3% yield whilst legume straw recorded 26.8%. Maize and groundnut straw recorded the highest yield of 37,323,264.16 and 12,495,288.96 tonnes respectively. Brong Ahafo region of Ghana had the highest maize straw yield with the Northern region recording readily availability of both cereals and legumes straw resources. The major re-use methods of straw in Ghana are as livestock feed, fertilizer, cooking fuel, for sale and as a substrate for mushroom production. We recommend strategies the government can adapt to develop policies geared towards the accurate recording of straw and their comprehensive utilization in Ghana. The efficient utilization of straw resources will reduce soil erosion, improve soil fertility, serve as feed for livestock, reduce pollution, generate biofuels plus generate employment to benefit the rural economy.

Hydrogen gas will be an essential energy carrier for global energy systems in the future. However, non-renewable sources account for 96% of the production. Food wastes have high hydrogen generation potential, which can positively influence global production and reduce greenhouse gas (GHG) emissions. The study evaluates the potential of food waste hydrogen-based power generation through biogas steam reforming and its environmental and economic impact in major Ghanaian cities. The results highlight that the annual hydrogen generation in Kumasi had the highest share of 40.73 kt, followed by Accra with 31.62 kt, while the least potential was in Tamale (3.41 kt). About 2073.38 kt was generated in all the major cities. Hydrogen output is predicted to increase from 54.61 kt in 2007 to 119.80 kt by 2030. Kumasi produced 977.54 kt of hydrogen throughout the 24-year period, followed by Accra with 759.76 kt, Secondi-Takoradi with 255.23 kt, and Tamale with 81.85 kt. According to the current study, Kumasi had the largest percentage contribution of hydrogen (47.15%), followed by Accra (36.60%), Secondi-Takoradi (12.31%), and Tamale (3.95%). The annual power generation potential in Kumasi and Accra was 73.24 GWh and 56.85 GWh. Kumasi and Accra could offset 8.19% and 6.36% of Ghana's electricity consumption. The total electricity potential of 3728.35 GWh could displace 17.37% of Ghana's power consumption. This electricity generated had a fossil diesel displacement capacity of 1125.90 ML and could reduce GHG emissions by 3060.20 kt CO₂ eq. Based on the findings, the total GHG savings could offset 8.13% of Ghana's carbon emissions. The cost of power generation from hydrogen is $ 0.074/kWh with an annual positive net present value of $ 658.80 million and a benefit-to-cost ratio of 3.43. The study lays the foundation and opens policy windows for sustainable hydrogen power generation in Ghana and other African countries.

Agricultural sensors are essential technologies for smart agriculture, which can transform non-electrical physical quantities such as environmental factors. The ecological elements inside and outside of plants and animals are converted into electrical signals for control system recognition, providing a basis for decision-making in smart agriculture. With the rapid development of smart agriculture in China, agricultural sensors have ushered in opportunities and challenges. Based on a literature review and data statistics, this paper analyzes the market prospects and market scale of agricultural sensors in China from four perspectives: field farming, facility farming, livestock and poultry farming and aquaculture. The study further predicts the demand for agricultural sensors in 2025 and 2035. The results reveal that China’s sensor market has a good development prospect. However, the paper garnered the key challenges of China’s agricultural sensor industry, including a weak technical foundation, poor enterprise research capacity, high importation of sensors and a lack of financial support. Given this, the agricultural sensor market should be comprehensively distributed in terms of policy, funding, expertise and innovative technology. In addition, this paper highlighted integrating the future development direction of China’s agricultural sensor technology with new technologies and China’s agricultural development needs.

Renewable energy is predicted to play a crucial role in the energy sector as transitioning from fossil fuels to biofuels is key to achieving carbon neutrality. The comprehensive utilization of livestock manure and crop residues as a viable source of biofuels can play a significant role in Ghana’s future energy system. This current study aims to examine and predict the biofuel potential in Ghana from animal manure and crop residues. The biogas-biomethane potential of animal manure is determined using anaerobic digestion technology, whereas crop residues’ bioethanol potential is assessed using computational and analytical approaches. The findings demonstrate that animal manure biogas potential is 237.72 normal million cubic meters (NMm³). The highest manure-biogas potential per animal is from cattle (27.15 Nm³) and pigs (18.15 Nm³), while the least contribution is from chickens (1.80 Nm³). In addition, the annual bioethanol production is 3.74 gigaliters (GL), and residues from maize (0.88 GL), yams (0.82 GL), and plantains (0.47 GL) had the largest share per annum. By 2100, Ghana has the potential to produce 1288.56 NMm³ of manure-based biogas which can offset 13.88% of liquefied petroleum gas (LPG) consumption. The biogas potential positively correlates with the biomethane potential of 901.99 NMm³. Furthermore, 91.85% of the 14.76 GL of bioethanol will be from food crop residues. This study provides critical information to lawmakers and energy planners with strategies to achieve energy security and minimize the ecological footprint in an optimistic scenario.