## 1 Introduction  
The energy used in aquaculture farms is the second important aspect in semi-intensive and intensive systems, caused by the cost of electricity for pumping and aeration; some authors report that the cost of energy generally represents between 10% and 15% of the total production costs [1]. However, in Mexico, aquaculture claim that the price of electricity is very high and is a reason why many farms close their operations. In this regard, the National Commission of Fisheries and Aquaculture (CONAPESCA) reported 458,260 GW/h of energy subsidies for the sector, which represented an amount of USD 9,488,197.89 for 504 producers in 29 states of the country [2; 3]. Although the Mexican government covered part of the energy costs, the coverage is still limited, since the set of national UPAs (Aquaculture Production Units) is larger. The cost of energy is a key factor in the sum of production costs in aquaculture, since electricity prices in commercial and industrial tariffs in Mexico are high, compared to other producing countries, being up to 134% without subsidy and 84% with subsidy for the agricultural sector, including aquaculture [4]. Currently, the cost per kilowatt/Hour (kW/h) in the commercial tariff where most of the UPAs in Mexico are located is the so-called PDBT (Small Demand Low Voltage) up to 25 kW of energy demand; its cost is USD 0.19 per kW/h, plus a fixed charge of USD 1.87 per month, regardless of energy consumption [5]. This subsidy is important mainly due to the fact that the aeration equipment operates 24 h a day, which has an impact on the operation of farms, especially those with a semi-intensive to intensive production system. A survey applied to 219 aquaculture farmers revealed that the cost of electricity per month (EC) in 41.13 % of the cases is a limiting factor to compete [6]. This aspect reveals that the cost of electricity in Mexican aquaculture farms is high, and an alternative is required to minimize this cost. Competitiveness in the aquaculture sector is threatened by the growing importation of Tilapia from the Asian continent, which has been increasing in recent years, leaving the Mexican aquaculturists at a disadvantage due to the low price of the product offered in Mexico [1], in addition to the problems associated with the recent COVID-19 pandemic, which has led to a decline in the sales of aquaculture products and a substantial increase in production costs. Faced with the inability to sell, aquaculturists have maintained cultured species by feeding them, due to declining demand and increased risks caused by confinement measures, disruption of supply chains, and uncertainty about the future, all of which are disruptions in the global market [7; 8; 9]. Water, feed and energy use is indispensable for the development of aquaculture; however, in these uncertain times, innovation is needed to mitigate these costs and support the recovery and competitiveness of small and medium-sized aquaculture enterprises (SMEs) in coastal, urban and rural areas [10; 11]. The pertinence and relevance of the research is to contribute to the acceleration of the penetration of On Grid-PV in the aquaculture sector to generate its own energy, reduce pressure on public spending on subsidies and help keep production costs low, ensuring energy and food security [1; 12; 13; 14]. On the other hand, in the scientific literature related to Nile Tilapia production, there is no evidence of studies that propose and demonstrate the technical, economic and environmental feasibility of using Photovoltaic Systems Connected to the Grid (On Grid-PV) to mitigate production costs, which in the case of aquaculture is the second most relevant cost [6; 13].