How, When, and Where? Assessing Renewable Energy Self-Sufficiency at the Neighborhood Level

Abstract

Self-sufficient decentralized systems challenge the centralized energy paradigm. Although scholars have assessed specific locations and technological aspects, it remains unclear how, when, and where energy self-sufficiency could become competitive. To address this gap, we develop a techno-economic model for energy self-sufficient neighborhoods that integrates solar photovoltaics (PV), conversion, and storage technologies. We assess the cost of 100% self-sufficiency for both electricity and heat, comparing different technical configurations for a stylized neighborhood in Switzerland and juxtaposing these findings with projections on market and technology development. We then broaden the scope and vary the neighborhood's composition (residential share) and geographic position (along different latitudes). Regarding how to design self-sufficient neighborhoods, we find two promising technical configurations. The "PV-battery-hydrogen" configuration is projected to outperform a fossil-fueled and grid-connected reference configuration when energy prices increase by 2.5% annually and cost reductions in hydrogen-related technologies by a factor of 2 are achieved. The "PV-battery" configuration would allow achieving parity with the reference configuration sooner, at 21% cost reduction. Additionally, more cost-efficient deployment is found in neighborhoods where the end-use is small commercial or mixed and in regions where seasonal fluctuations are low and thus allow for reducing storage requirements.

Energy self-sufficient households with photovoltaics and electric vehicles are feasible in temperate climate

“…Inverter efficiency 99% [23] Performance ratio 0.9 [24] Solar irradiation, rooftop 1,000 kWh/m 2 /year [25] Solar irradiation, facade 800 kWh/m 2 /year [10], [26], [25] [10], [28], [29], [30], [31] Rooftop slope 35˚35˚ [32], [ DHW demand in 2050 10.9 kWh/m 2 ; -26% compared to 2020 [18] 12.6 kWh/m 2 ; -26% compared to 2020 [18] [14], [19], [29], [30], [31], [35] DHW efficiency factor in 2050 3.5; +22% compared to 2020 [18] 3.5; +22% compared to 2020 [18] [18], [36]…”

“…The energy demand for each case is quantified on a monthly basis to capture the fact that lighting and space heating demand vary seasonally [38]. Regarding dimension 1, the household types need a specific size, which we base on adjusted data from measurements performed by Grosspietsch, Thommes (10). Annual energy demand of SFHs and MFBs for domestic hot water (DHW) was calculated by taking the mean of reported future demand from the sources given in Table 2, in order to arrive at a robust estimate of potential demand reductions.…”

“…An electrolyzer efficiency of 80% is thus reasonable in 2050. The efficiency of PEM fuel cells is provided by various sources [10,49,60]. Based on positive efficiency estimations by Miotti, Hofer (49) of 52% for 2030, we assume this value to be reached in 2050.…”

“…t = 1 is the year 2050. We assume a time horizon of 20 years and set the discount rate i to 4% in 2050, which represents the contemporary average discount rate of residential consumers [61]. Eq 4 is based on the LCOE definition of Hernandez-Moro and Martinez-Duart [62] and comprises investment costs (capital costs and balance-of-system (BOS) costs) and operation and maintenance (O&M) costs.…”

“…Some of the studies outlined in the table help us build a comprehensive picture of how individual components in a self-sufficient household work, e.g. by optimizing combined PV and battery deployments [10][11][12][13]. Other studies analyze individual cases of net zero-energy buildings [14,15], but these studies do not include considerations of electrified mobility and how that would affect building-level self-sufficiency.…”