Testing the Applicability of “Ecologically Friendly” Energy Sources in Household Electricity Consumption in Bulgaria

Abstract

The EU’s “Green Deal” plans a carbonfree energy mix, neglecting nuclear energy, despite high social costs. Photovoltaic and wind power plants lack proper solutions for storing the excessive electricity. Their EROI is still lower compared to that of conventional sources. A complementary pair of combined cycle gas turbines (CCGT) and photovoltaics is a good solution for regular electricity supplies for households at affordable prices. Such a model is based on consumption data in Ruse (Bulgaria), delivered by Nicola Mihaylov et al. It also includes data, delivered by RIS Elektro OOD – a solar park operator. Matching consumption fluctuations with production fluctuations gives the following: A 1 MW CCGT that supplies up to 1,600-1700 households is combined with a 250 kW photovoltaic park. The calculations show that because of the park the CCGT should operate with lower EROI and "green surcharge" in the consumers’ price. The optimal solution for energy deliveries requires a better balance between political, technical and economic factors.

Overview of Energy Harvesting Technologies Used in Road Vehicles

“…On the other hand, the expected share of RES (photovoltaics and wind farms) at the level of over 50% in the total energy mix is questionable due to their main and obvious disadvantage-i.e., high dependence on weather conditions. It is known that photovoltaic installations cannot generate electricity at night; however, during the day, the amount of solar radiation also varies, especially when it is located in the middle latitudes where EU countries are situated [36]. The area with relatively constant winds is the coastal zone and the Central European Plain; on the rest of the continent there are the same problems as with photovoltaics.…”

“…The spread of pumped-storage hydro power plants is favored by the surplus of energy generated at night by stable nuclear power plants, i.e., their efficiency is high exclusively in the complementary pair. With the exception of pumped-storage, all other methods have low energy storage capacity [36], but progress in the field of batteries could be a breakthrough in this sector. In the case of batteries, potential shortages of lithium and other metals used in the production of batteries may be a threat.…”