Substitution Of Fossil Fuels Research Articles

Growth in floor area: the blind spot in cutting carbon

While most efforts to combat climate change are focussed on energy efficiency and substitution of fossil fuels, growth in the built environment remains largely unquestioned. Given the current climate emergency and increasing scarcity of global resources, it is imperative that we address this ‘blind spot’ by finding ways to support required services with less resource consumption.There is now long overdue recognition to greenhouse gas emissions ‘embodied’ in the production of building materials and construction, and its importance in reaching targets of net zero carbon by 2050. However, there is a widespread belief that we can continue to ‘build big’, provided we incorporate energy saving measures and select ‘low carbon materials’ − ignoring the fact that excessive volume and area of buildings may outweigh any carbon savings. This is especially the case with commercial real estate.As the inception and planning phases of projects offer most potential for reduction in both operational and embodied carbon, we must turn our attention to previously overlooked options such as ‘build nothing’ or ‘build less’. This involves challenging the root cause of the need, exploring alternative approaches to meet desired outcomes, and maximising the use of existing assets. If new build is required, this should be designed for adaptability, with increased stewardship, so the building stock of the future will be a more valuable and useable resource.This points to the need for increased understanding and application of the principles of strategic asset management, hitherto largely ignored in sustainability circles, which emphasize a close alignment of assets with the services they support.Arguably, as the built environment consumes more material resources and energy than any other sector, its future configuration may be critical to the future of people and the planet. In this regard, this paper seeks to break new ground for deeper exploration.

Growth in floor area: the blind spot in cutting carbon

While most efforts to combat climate change are focussed on energy efficiency and substitution of fossil fuels, growth in the built environment remains largely unquestioned. Given the current climate emergency and increasing scarcity of global resources, it is imperative that we address this “blind spot” by finding ways to support required services with less resource consumption. There is now long overdue recognition to greenhouse gas emissions “embodied” in the production of building materials and construction, and its importance in reaching targets of net zero carbon by 2050. However, there is a widespread belief that we can continue to “build big”, provided we incorporate energy saving measures and select “low carbon materials” – ignoring the fact that excessive volume and area of buildings may outweigh any carbon savings. This is especially the case with commercial real estate. As the inception and planning phases of projects offer most potential for reduction in both operational and embodied carbon, we must turn our attention to previously overlooked options such as “build nothing” or “build less”. This involves challenging the root cause of the need, exploring alternative approaches to meet desired outcomes, and maximising the use of existing assets. If new build is required, this should be designed for adaptability, with increased stewardship, so the building stock of the future will be a more valuable and useable resource. This points to the need for increased understanding and application of the principles of strategic asset management, hitherto largely ignored in sustainability circles, which emphasize a close alignment of assets with the services they support. Arguably, as the built environment consumes more material resources and energy than any other sector, its future configuration may be critical to the future of people and the planet. In this regard, this paper seeks to break new ground for deeper exploration.

Optimation of <i>Spirulina</i> sp. Growth in Walne Media with Variation of Urea and NaHCO3 Supplements

One alternative biofuel to substitute fossil fuels is bioethanol. Microalgae Spirulina sp. contains high carbohydrates, which has 17-25% potential to produce bioethanol. Urea and NaHCO3 can be used as additional nutrients sources of nitrogen and carbon to Spirulina sp. cultivation. Deficiency of nitrogen causing the cell’s enzymes change that shown through decreased lipid and chlorophyll synthesis. While deficiency of carbon can affect the growth rate. In this research, the growth rate of Spirulina sp. is analyzed using Optical Density (OD) method. The growth rate calculation is used to measure the growth of microalgae cells shown in the growth curve. This was a laboratory-scale method using CRD with 4 treatments and 5 replications namely treatment A addition of 0.36 g/500 ml urea without addition of NaHCO3, treatment B addition of 0.043 g/500 ml NaHCO3 without addition of urea, treatment C addition of 0.36 g/500 ml urea and 0.043 g/500 ml NaHCO3, and control without addition of urea or NaHCO3. The results indicated that addition of urea and NaHCO3 didn’t affect to OD and Spirulina sp. growth rate. The highest growth rate was treatment A with 0.00906/day of growth rate followed by treatment C which has 0.00865/day of growth rate. Treatment B and control treatment (K) showed a low growth rate. The maximum OD value obtained in treatment C was 0.674 cells/ml on the 10th day. This research can be used as the reference to larger scale of Spirulina sp. cultivation in the field of bioethanol production.

Temperature and emissivity measurements from combustion of pine wood, rice husk and fir wood using flame emission spectrum

Biomass combustion for heat and power generation is one of the best ways for substituting fossil fuels. It is necessary to develop in situ temperature and emissivity measurement technology for biomass volatile flame. In this study, combustion experiments on three biomass pellets of pine wood, rice husk and fir wood were carried out in a laboratory biomass burner at two A/F flowrates. A multi-wavelength radiation thermometry method was proposed to calculate temperature and wavelength-dependent emissivity based on Rayleigh approximation. The results showed that the temperature and emissivity of pine wood combustion were higher than those of rice husk and fir wood volatile flames. Though the emissivity of rice husk was less than that of fir wood, the temperature of rice husk combustion was higher than that of fir wood due to the latter's higher moisture content. The temperatures measured by the spectrometer system agreed well with the thermocouple data. The normalized emissivities of the three different biomass show the same trend, indicating the radiative properties of biomass volatile flames do not change with biomass species and combustion conditions.

The reservoir network: A new network topology for district heating and cooling

Thermal district networks are effective solutions to substitute fossil fuels with renewable energy sources for heating and cooling. Moreover, thermal networking of buildings allows energy efficiency to be further increased. The waste heat from cooling can be reused for heating in thermal district systems. Because of bidirectional energy flows between prosumers, thermal networks require new hydraulic concepts. In this work, we present a novel network topology for simultaneous heating and cooling: the reservoir network. The reservoir network is robust in operation due to hydraulic decoupling of transfer stations, integrates heat sources and heat sinks at various temperature levels and is flexible in terms of network expansion.We used Modelica simulations to compare the new single-pipe reservoir network to a basecase double-pipe network, taking yearly demand profiles of different building types for heating and cooling. The electric energy consumed by the heat pumps and circulations pumps differs between the reservoir and base case networks by less than 1%. However, if the reservoir network is operated with constant instead of variable mass flow rate, the total electrical consumption can increase by 48% compared to the base case. As with any other network topology, the design and control of such networks is crucial to achieving energy efficient operation.Investment costs for piping and trenching depend on the district layout and dimensioning of the network. If a ring layout is applied in a district, the reservoir network with its single-pipe configuration is more economical than other topologies. For a linear layout, the piping costs are slightly higher for the reservoir network than for the base case because of larger pipe diameters.

Growth in floor area: the blind spot in cutting carbon

While most efforts to combat climate change are focussed on energy efficiency and substitution of fossil fuels, growth in the built environment remains largely unquestioned. Given the current climate emergency and increasing scarcity of global resources, it is imperative that we address this ‘blind spot’ by finding ways to support required services with less resource consumption.There is now long overdue recognition to greenhouse gas emissions ‘embodied’ in the production of building materials and construction, and its importance in reaching targets of net zero carbon by 2050. However, there is a widespread belief that we can continue to ‘build big’, provided we incorporate energy saving measures and select ‘low carbon materials’ − ignoring the fact that excessive volume and area of buildings may outweigh any carbon savings. This is especially the case with commercial real estate.As the inception and planning phases of projects offer most potential for reduction in both operational and embodied carbon, we must turn our attention to previously overlooked options such as ‘build nothing’ or ‘build less’. This involves challenging the root cause of the need, exploring alternative approaches to meet desired outcomes, and maximising the use of existing assets. If new build is required, this should be designed for adaptability, with increased stewardship, so the building stock of the future will be a more valuable and useable resource.This points to the need for increased understanding and application of the principles of strategic asset management, hitherto largely ignored in sustainability circles, which emphasize a close alignment of assets with the services they support.Arguably, as the built environment consumes more material resources and energy than any other sector, its future configuration may be critical to the future of people and the planet. In this regard, this paper seeks to break new ground for deeper exploration.

Interfuel substitution, hydroelectricity consumption and CO2 emissions mitigation in Malaysia: evidence from a transcendental logarithm (trans-log) cost function framework.

The main objective of this paper is to estimate the interfuel substitution elasticities between hydropower and the fossil fuels of coal and natural gas used in the generation of electricity for Malaysia. Due to the violation of the assumption behind the ordinary least squares (OLS) method on account of the correlated error terms in the system of equations, the econometrics techniques of seemingly unrelated regression (SUR) was adopted to obtain the parameter estimates using dataset that covers the period 1988 to 2016. The main finding is that there exists substantial substitution possibility between hydropower and fossil fuels in the generation of electricity for Malaysia. CO2 emissions mitigation scenarios were also conducted to explore the possible effects of substituting fossil fuels for hydropower to generate electricity. The results show that switching from high carbon-emitting fuels to renewable energy such as hydropower will substantially reduce CO2 emission and assist the country towards achieving the carbon emissions reduction targets. Policy recommendations are offered in the body of the manuscript.

Simultaneous lipid production for biodiesel feedstock and decontamination of sago processing wastewater using Candida tropicalis ASY2

BackgroundWithout sufficient alternatives to crude oil, as demand continues to rise, the global economy will undergo a drastic decline as oil prices explode. Dependence on crude oil and growing environmental impairment must eventually be overcome by creating a sustainable and profitable alternative based on renewable and accessible feedstock. One of the promising solutions for the current and near-future is the substitution of fossil fuels with sustainable liquid feedstock for biofuel production. Among the different renewable liquid feedstock’s studied, wastewater is the least explored one for biodiesel production. Sago wastewater is the byproduct of the cassava processing industry and has starch content ranging from 4 to 7%. The present investigation was aimed to produce microbial lipids from oleaginous yeast, Candida tropicalis ASY2 for use as biodiesel feedstock and simultaneously decontaminate the sago processing wastewater for reuse. Initial screening of oleaginous yeast to find an efficient amylolytic with maximum lipid productivity resulted in a potent oleaginous yeast strain, C. tropicalis ASY2, that utilizes SWW as a substrate. Shake flask experiments are conducted over a fermentation time of 240 h to determine a suitable fatty acid composition using GC-FID for biodiesel production with simultaneous removal of SWW pollutants using ASY2.ResultsThe maximum biomass of 0.021 g L−1 h−1 and lipid productivity of 0.010 g L−1 h−1 was recorded in SWW with lipid content of 49%. The yeast strain degraded cyanide in SWW (79%) and also removed chemical oxygen demand (COD), biological oxygen demand (BOD), nitrate (NO3), ammoniacal (NH4), and phosphate (PO4) ions (84%, 92%, 100%, 98%, and 85%, respectively). GC-FID analysis of fatty acid methyl esters (FAME) revealed high oleic acid content (41.33%), which is one of the primary fatty acids for biodiesel production.ConclusionsIt is evident that the present study provides an innovative and ecologically sustainable technology that generates valuable fuel, biodiesel using SWW as a substrate and decontaminates for reuse.

Economic potential for substitution of fossil fuels with liquefied biomethane in Swedish iron and steel industry – Synergy and competition with other sectors

In Sweden, the iron and steel industry (ISI) is a major source of greenhouse gas (GHG) emissions. Most of the emissions result from the use of fossil reducing agents. Nevertheless, the use of fossil fuels for other purposes must also be eliminated in order to reach the Swedish emissions reduction targets. In this study, we investigate the possibility to replace fossil gaseous and liquid fuels used for heating in the ISI, with liquefied biomethane (LBG) produced through gasification of forest residues. We hypothesize that such utilization of fuels in the Swedish ISI is insufficient to independently drive the development of large-scale LBG production, and that other sectors demanding LBG, e.g., for transportation, can be expected to influence the economic potential for the ISI to switch to LBG. The paper investigates how demand for LBG from other sectors can contribute to, or prevent, a phase-out of fossil fuels used for heating purposes in the ISI under different future energy market scenarios, with additional analysis of the impact of a CO2 emissions charge. A geographically explicit cost-minimizing biofuel production localization model is combined with heat integration and energy market scenario analysis. The results show that from a set of possible future energy market scenarios, none yielded more than a 9% replacement of fossil fuels used for heating purposes in the ISI, and only when there was also a demand for LBG from other sectors. The scenarios corresponding to a more ambitious GHG mitigation policy did not achieve higher adoption of LBG, due to corresponding higher biomass prices. A CO2 charge exceeding 200 EUR/tonCO2 would be required to achieve a full phase-out of fossil fuels used for heating purposes in the ISI. We conclude that with the current policy situation, substitution of fossil fuels by LBG will not be economically feasible for the Swedish ISI.

Global carbon surcharge for the reduction of anthropogenic emission of carbon dioxide

BackgroundMany governments take the view that voluntary national targets to reduce greenhouse gas emissions are sufficient to avoid negative climate effects. In the absence of independent verification, however, pledges are unlikely to be sufficient for a rapid and strong reduction of emissions. It is often claimed that a global carbon tax could be an effective instrument. However, such a tax is difficult to set and to collect, especially in countries with poor administrative infrastructure.ResultsHere, we formulate and discuss a novel approach, the Global Carbon Surcharge (GCS), that mimics a carbon tax but does not require tax collection by governments. We define GCS as a requirement or a voluntary commitment encompassing all companies extracting carbon-carrying raw materials, namely coal, oil, gas and limestone, with the aim to burden their extraction with costs proportional to their carbon intensity. GCS mandates all companies to store these materials immediately after mining for a given period of time in the vicinity of the production site. Thereby, GCS generates additional costs that propagate through all sectors of the global economy. We elucidate how the investment costs for the storage infrastructure translate into surcharges on the raw materials.ConclusionsWe show that by a proper choice of the storage time and the size of the storage unit, GCS becomes equivalent to a carbon tax in the range between 50 and 100 € per ton of CO2 that is assumed to be necessary for the transition to a carbon-neutral energy system. An attractive feature of GCS is that it can be verified, in particular by citizens themselves, using publicly available satellite data. Finally, if compulsory storage is coupled to blockchain-based smart contracts and a mandatory (expensive) mining of cryptocurrency, GCS can be operated without governmental protectionism, corruption and fraud. However, the main uncertainties of the GCS approach lie in the substantial expansion of infrastructure and the fact that the induced price effects must be sufficient to achieve a rapid and far-reaching substitution of fossil fuels.

US energy system transitions under cumulative emissions budgets

Cumulative emissions budgets are increasingly being used by decision-makers and analysts to understand emissions reductions and associated transitions in the context of long-term goals such as limiting global mean temperature increase over the century to 1.5 or 2 °C. While previous studies have explored the implications of such budgets for the global economy, few studies have conducted regional- and national-level analyses. This paper explores budgets through 2050 consistent with the 1.5 and 2 °C long-term temperature goals in the context of the USA. We employ a state-level model of the USA embedded within a global human-Earth system model (GCAM-USA) to study the implications of such budgets for the US energy system. Our results show that achieving the stringent budgets entails accelerated deployment of energy conserving technology, almost complete decarbonization of the power sector, increased electrification of buildings and industrial end-use sectors, and decarbonization of transport employing a combination of electrification and the substitution of fossil fuels for bioenergy. We also find substantial state-level differences in the relative roles of these decarbonization strategies. Furthermore, our results highlight that increased ambition in the near term will be valuable in setting the stage for smoother transformations in the future to achieve stringent budgets.

Energy Efficiency of a Heat Pump System: Case Study in Two Pig Houses

This study describes a 70-day investigation of three identical groundwater heat pumps (GWHP) for heating two pig houses located on the same farm in West Germany. Two of the three GWHPs were installed in a piglet-rearing barn, the third in a farrowing barn. All three heat pumps were fed from the same extraction well. The aim of this study was firstly the empirical performance measurement of the GWHP systems and secondly the energetic evaluation of the systems on barn level by calculating the coefficient of performance (COP). Three different assessment limits were considered in order to better identify factors influencing the COP. In total, the heat pumps supplied thermal energy of 47,160 kWh (piglet-rearing barn) and 36,500 kWh (farrowing barn). Depending on the assessment limit considered, the COP in piglet-rearing barn and farrowing barn ranged between 2.6–3.4 and 2.5–3.0, respectively. A significant factor influencing the COP is the amount of electrical current required to operate the groundwater feeding pump. The average groundwater flow rate was 168.4 m3 d−1 (piglet-rearing barn) and 99.1 m3 d−1 (farrowing barn). In conclusion, by using energy from groundwater, GWHPs have the potential to substitute fossil fuels, thus saving them and avoiding CO2 emissions.

The effect of the addition of TiO2 nanoparticles to coal-water fuel on its thermophysical properties and combustion parameters

Coal-water fuel is a promising substitution of conventional fossil fuels for the countries, where clean energy sources like wind, solar, etc. cannot cover energy demand. However, this fuel has a lot of specifics for preparation, transportation, and combustion. Issues with coal-water fuel combustion can be solved with the use of fuel activation. The catalytic activation of the coal-water fuel produced from coal of different metamorphic stages with the help of titanium dioxide nanoparticles was experimentally studied. The research suggests that the addition of the titanium dioxide nanoparticles in 0.5–4% wt. increases the coal-water fuel thermal conductivity by 9–17% while the value of heat capacity decreases by 12–23%. Also, this addition decreases time delay before fuel ignition by 20–22% and a total time of the fuel droplet burning by 15%; increases maximum temperature of the volatiles combustion by 8–10%; and increases combustion completeness as well. For the first time, the optimal value of the nanoparticles additive content has been found.

Enhancing the solar water splitting activity of TiO2 nanotube-array photoanode by surface coating with La-doped SrTiO3

Photoelectrochemical water splitting has been considered one of the most promising alternatives for the substitution of fossil fuels with a clean and renewable fuel, such as H2. Two of the most studied photocatalysts for such application are titanium dioxide and strontium titanate due to their favourable photoactivity, robustness and availability; although specific limitations have hindered their large-scale implementations. In this investigation, we produced photoanodes comprising heterojunctions of TiO2 nanotubes and lanthanum-doped SrTiO3 for the photoelectrochemical split of water, under simulated solar irradiation. A thin layer of SrTiO3 formed on the surface of TiO2 nanotubes through a hydrothermal route was effective in promoting the electron-hole separation at the interface, leading to a photocurrent density enhancement from 58.9 to 109.4 μA cm−2 (at 1.23 V vs RHE). The charge transfer resistance at the solid/liquid interface was substantially reduced, according to electrochemical impedance spectroscopy measurements. Further photoactivity increase was achieved by doping the SrTiO3 overlayer with La3+. This is the first time the application of such La:SrTiO3/TiO2 nanocomposite in sustainable energy production is reported. The doping with 10 mol% of La3+ into the Sr2+ sites enhanced the photoelectrochemical response to 144.2 μA cm−2 (1.23 V vs RHE) due to the suppression of deep trapping states related to formed SrO species.

Growth in floor area: the blind spot in cutting carbon

While most efforts to combat climate change are focussed on energy efficiency and substitution of fossil fuels, growth in the built environment remains largely unquestioned. Given the current climate emergency and increasing scarcity of global resources, it is imperative that we address this ‘blind spot’ by finding ways to support required services with less resource consumption.There is now long overdue recognition to greenhouse gas emissions ‘embodied’ in the production of building materials and construction, and its importance in reaching targets of net zero carbon by 2050. However, there is a widespread belief that we can continue to ‘build big’, provided we incorporate energy saving measures and select ‘low carbon materials’ − ignoring the fact that excessive volume and area of buildings may outweigh any carbon savings. This is especially the case with commercial real estate.As the inception and planning phases of projects offer most potential for reduction in both operational and embodied carbon, we must turn our attention to previously overlooked options such as ‘build nothing’ or ‘build less’. This involves challenging the root cause of the need, exploring alternative approaches to meet desired outcomes, and maximising the use of existing assets. If new build is required, this should be designed for adaptability, with increased stewardship, so the building stock of the future will be a more valuable and useable resource.This points to the need for increased understanding and application of the principles of strategic asset management, hitherto largely ignored in sustainability circles, which emphasize a close alignment of assets with the services they support.Arguably, as the built environment consumes more material resources and energy than any other sector, its future configuration may be critical to the future of people and the planet. In this regard, this paper seeks to break new ground for deeper exploration.

DETERMINATION OF KINETIC PARAMETERS OF CHEERY TREE PYROLYSIS USING KISSINGER METHOD

In the global quest for substitution of fossil fuels, biomass is regarded as one of the most promising alternatives. Thermochemical conversion is one of the dominant biomass-to-energy processing routes with pyrolysis as one of the options that gained importance in recent years. In this paper pyrolysis experiments of cheery tree samples were performed. The objective of this research was to determine selected physical and chemical properties of cheery related to thermochemical conversion. The samples were pyrolysed in a thermogravimetric analyzer in an inert, nitrogen, atmosphere at four different heating rates 1, 2, 5 and 10 °C/min. Pyrolysis occurred, as expected, in three step: loss of moisture and light volatiles, active and passive pyrolysis. With an increase in heating rate a lateral shift of the maximum rate of weight loss for the thermal decomposition to higher temperatures was observed, as well as an increase in the amount of residual char. Moreover, kinetic studies were performed using the Kissinger method. The activation energy was calculated to be 155.26 kJ/mol, while the pre-exponential factor was 1.685×1012 min-1. Obtained results are comparable to values reported in literature. Kissinger method is straightforward and offers the possibility for fast and reliable determination of kinetic parameters.

Primer energetski efikasnog korišćenja subgeotermalnog resursa za potrebe klimatizacije prodajnog kompleksa

For the air-conditioning of the IKEA sales complex in Belgrade, the exploitation of groundwater, as a subgeothermal resource, was carried out, using a heat pump. The groundwater from a karst aquifer is abstracted by the three drilled wells, the depths of which are 87-103m. Based on the results of the 1-year trial exploitation, in the period August 2017-July 2018, balance reserve of the groundwater is 10.8 l/s, with temperatures in the range 22.0-22.9 0C, which gives the nominal available thermal power of the system of 774 kWt. The applied air-conditioning solution can be assessed as energy efficient, due to the efficiency of the water-water heat pump system, as well as to an environmental contribution, by the substitution of fossil fuels. Preliminary economic analysis shows that total financial investments in the system, compared with the conventional alternative solution, are paid after less than six years.

First Results from a Solar-Biomass Hybrid System for the Production of Solar Carbon

Solar energy as well as biomass energy techniques suffers from disadvantages, which in some cases limit their potential for substituting fossil fuels. For instance, solar energy is difficult to store, and many kinds of biomass are not suited for combustion, in spite of the fact that they have high energy contents. We describe and industrial size system, which has the goal of overcoming some of these limitations by combining solar- and biomass power. This is achieved by roasting residual biomass by means of hot air provided by solar power only. The solar power is collected by three “Linear Mirror” solar concentrator, they are designed to achieve high efficiency also at northern latitudes. Each one is equipped with an innovative solar-air heat exchanger. The hot air is delivered to a roasting device filled with humid residual biomass. We report the performance of this system from a first commissioning run. The system is intended to help create a closed-cycle economy by means of transforming waste biomasses to a high-quality combustible.

The Influence of Pressure-Swing Conditioning Pre-Treatment of Cattle Manure on Methane Production.

Cattle manure is an agricultural residue, which could be used as source to produce methane in order to substitute fossil fuels. Nevertheless, in practice the handling of this slowly degradable substrate during anaerobic digestion is challenging. In this study, the influence of the pre-treatment of cattle manure with pressure-swing conditioning (PSC) on the methane production was investigated. Six variants of PSC (combinations of duration 5 min, 30 min, 60 min and temperature 160 °C, 190 °C) were examined with regards to methane yield in batch tests. PSC of cattle manure showed a significant increase up to 109% in the methane yield compared to the untreated sample. Kinetic calculations proved also an enhancement of the degradation speed. One PSC-variant (190 °C/30 min) and untreated cattle manure were chosen for comparative fermentation tests in continuously stirred tank reactors (CSTR) in lab-scale with duplicates. In the continuous test a biogas production of 428 mL/g volatile solids (VS) (54.2% methane) for untreated manure was observed and of 456 mL/g VS (53.7% methane) for PSC-cattle-manure (190 °C/30 min). Significant tests were conducted for methane yields of all fermentation tests. Furthermore, other parameters such as furfural were investigated and discussed.

Fossil Fuel Substitution with Renewables for Electricity Generation – Effects on Sustainability Goals

The substitution of fossil fuel power plants with renewable units will lead to a profound reduction of CO2 emissions and will assist in evading the Global Climate Change. Using demand data from the electricity grid of Texas, this paper develops a scenario for the substitution of coal, at first, and of all fossil fuel power plants, secondly, in the entire State of Texas. Meeting the electricity demand of the grid with renewables, makes it necessary to develop significant energy storage capacity in addition to the renewable – wind and solar – installations. Because of the lower pant capacity factors of wind and solar units, the calculations show that significantly higher renewable power capacity must be built than the current capacity of the fossil fuel units to be substituted. Also, that a substantial fraction of the generated energy is lost in the storage-recovery processes. All these factors are expected to increase the price of electricity paid by the consumers. Ahis will have an impact on the less affluent segments of the population and – if ignored by national energy policies – will affect the goal to reduce inequality within and among countries.