Maximizing the value of customer-sited PV systems using storage and controls

This paper determines how the value of customer-sited PV can be increased with battery storage by enhancing the load management and outage protection attributes of PV. Case studies in San Jose, CA and Long Island, NY for residential and commercial PV applications are used for a quantitative illustration of storage value enhancement. Results indicate that: (1) a small amount of storage for local load control and a larger amount of storage for emergency load protection significantly increases the value of distributed PV to the customer; (2) the value of PV combined with emergency storage exceeds the sum of the value of these options implemented separately; and (3) there is a potential opportunity to use dispersed PV + storage to enhance grid security (capturing this value, however, will require regulatory and policy changes).     

Review of the performance of residential PV systems in Belgium

The main objective of this paper is to review the state of the art of residential PV systems in Belgium by the analysis of the operational data of 993 installations. For that, three main questions are posed: how much energy do they produce? What level of performance is associated to their production? Which are the key parameters that most influence their quality? This work brings answers to these questions. A middling commercial PV system, optimally oriented, produces a mean annual energy of 892 kWh/kW_p. As a whole, the orientation of PV generators causes energy productions to be some 6% inferior to optimally oriented PV systems. The mean performance ratio is 78% and the mean performance index is 85%. That is to say, the energy produced by a typical PV system in Belgium is 15% inferior to the energy produced by a very high quality PV system. Finally, on average, the real power of the PV modules falls 5% below its corresponding nominal power announced on the manufacturer's datasheet. Differences between real and nominal power of up to 16% have been detected.     

Review of the performance of residential PV systems in France

The main objective of this paper is to review the state of the art of residential PV systems in France. This is done analyzing the operational data of 6868 installations. Three main questions are posed. How much energy do they produce? What level of performance is associated to their production? Which are the key parameters that most influence their quality? During the year 2010, the PV systems in France have produced a mean annual energy of 1163 kWh/kW_p. As a whole, the orientation of PV generators causes energy productions to be some 7% inferior to optimally oriented PV systems. The mean Performance Ratio is 76% and the mean Performance Index is 85%. That is to say, the energy produced by a typical PV system in France is 15% inferior to the energy produced by a very high quality PV system. On average, the real power of the PV modules falls 4.9% below its corresponding nominal power announced on the manufacturer's datasheet. A brief analysis by PV modules technology has led to relevant observations about two technologies in particular. On the one hand, the PV systems equipped with heterojunction with intrinsic thin layer (HIT) modules show performances higher than average. On the other hand, the systems equipped with the copper indium (di)selenide (CIS) modules show a real power that is 16% lower than their nominal value.     

The impact of rate design and net metering on the bill savings from distributed PV for residential customers in California

Net metering has become a widespread mechanism in the U.S. for supporting customer adoption of distributed photovoltaics (PV), but has faced challenges as PV installations grow to a larger share of generation in a number of states. This paper examines the value of the bill savings that customers receive under net metering, and the associated role of retail rate design, based on a sample of approximately two hundred residential customers of California's two largest electric utilities. We find that the bill savings per kWh of PV electricity generated varies by more than a factor of four across the customers in the sample, which is largely attributable to the inclining block structure of the utilities' residential retail rates. We also compare the bill savings under net metering to that received under three potential alternative compensation mechanisms, based on California's Market Price Referent (MPR). We find that net metering provides significantly greater bill savings than a full MPR-based feed-in tariff, but only modestly greater savings than alternative mechanisms under which hourly or monthly net excess generation is compensated at the MPR rate.     

Evaluating the limits of solar photovoltaics (PV) in electric power systems utilizing energy storage and other enabling technologies

In this work, we evaluate technologies that will enable solar photovoltaics (PV) to overcome the limits of traditional electric power systems. We performed simulations of a large utility system using hourly solar insolation and load data and attempted to provide up to 50% of this system's energy from PV. We considered several methods to avoid the limits of unusable PV that result at high penetration due to the use of inflexible baseload generators. The enabling technologies considered in this work are increased system flexibility, load shifting via demand responsive appliances, and energy storage.     

An analysis of energy conservation possibilities in the residential sector in New Zealand

A model which simulates residential energy use in New Zealand until the year 2000 has been developed. This paper describes some of the energy conservation possibilities and their effect on energy use for space and water heating. an engineering analysis made to determine the effect of various factors on energy use for space heating is first described. the information gained from many computer simulations is used to develop a quantitative relationship between space heating energy and major determinants—climatic location, building type and intensity of use. Results from an engineering analysis of a water heating unit are used to establish the energy savings due to improved cylinder insulation and lower storage temperature. A solar space and water heating system is analysed to determine the fraction of total heating load that can be met by harnessing solar energy. the analyses demonstrate that the potential of conservation measures to reduce energy use can be substantial—by raising the insulation level on the building and on the water heating cylinder, by lowering the water storage temperature, and by installing an optimized solar heating system, the energy requirement can be reduced to 0·37 times what it is today for a typical uninsulated home.     

Utilization of solar–hydrogen energy in the UAE to maintain its share in the world energy market for the 21st century

A preliminary solar–hydrogen energy system for the United Arab Emirates (UAE) has been proposed to bridge the gap between oil and natural gas demand and supply in the 21st century, and to meet the country's share in the energy market. In our study, we quantitatively consider the benefits of such an energy system on the overall energy situation in the UAE. The variables considered include population, energy demand, energy production, income from sales of fossil fuels and hydrogen energy, photovoltaics area, and total land area required for installing such a system. Our study indicated that the UAE would fail to meet its share in the oil market demand by the year 2015, while in the case of natural gas it will be by the year 2042. In order to maintain its share in the world energy market, we propose that hydrogen be gradually introduced to meet the demand. The income generated by hydrogen energy would account for 90% of the nation's total income if such a system were utilized. Our analysis could be greatly influenced by several factors such as future government projects related to fossil fuel production and increasing diversification in the economy of the country.     

Impact of energy policy instruments on the estimated level of underlying energy efficiency in the EU residential sector

The promotion of energy efficiency is seen as one of the top priorities of EU energy policy (EC, 2010). In order to design and implement effective energy policy instruments, it is necessary to have information on energy demand price and income elasticities in addition to sound indicators of energy efficiency. This research combines the approaches taken in energy demand modelling and frontier analysis in order to econometrically estimate the level of energy efficiency for the residential sector in the EU-27 member states for the period 1996 to 2009. The estimates for the energy efficiency confirm that the EU residential sector indeed holds a relatively high potential for energy savings from reduced inefficiency. Therefore, despite the common objective to decrease ‘wasteful’ energy consumption, considerable variation in energy efficiency between the EU member states is established. Furthermore, an attempt is made to evaluate the impact of energy-efficiency measures undertaken in the EU residential sector by introducing an additional set of variables into the model and the results suggest that financial incentives and energy performance standards play an important role in promoting energy efficiency improvements, whereas informative measures do not have a significant impact.     

Evaluating the influence of increasing block tariffs in residential gas sector using agent-based computational economics

Designing a desirable increasing block tariff for the residential gas retail market has been a challenging task for regulated utilities, especially in China. To deal with such problems, in this paper, we establish an agent-based, computational economics system to provide a formal evaluation of the direct and indirect influences of several issued increasing block tariffs in the residential gas market. Moreover, a comprehensive demand response behaviour model has been improved in term of price elasticity, while still coping with income levels and complex social environment. We also compute and compare the outcomes of several increasing block tariffs with the initial flat tariff by running the system on a test-case using real-world data from a middle-scale gas retail market in Wuhan. The results indicate that there is an appropriate increasing block gas tariff scheme that has greater ability to improve social equity while still ensuring operator revenue and promoting gas conservation. In order to offset the limitations of the proposed increasing block tariffs, the regulator should adopt some complementary measures, such as applying appropriate policies targeting the intended consumers, and allowing large families to obtain extra allowance of volume.     

Prioritizing investment in residential energy efficiency and renewable energy—A case study for the U.S. Midwest

Residential building energy use is an important contributor to greenhouse gas emissions and in the United States represents about 20% of total energy consumption. A number of previous macro-scale studies of residential energy consumption and energy-efficiency improvements are mainly concerned with national or international aggregate potential savings. In this paper we look into the details of how a collection of specific homes in one region might reduce energy consumption and carbon emissions, with particular attention given to some practical limits to what can be achieved by upgrading the existing residential building stock. Using a simple model of residential, single-family home construction characteristics, estimates are made for the efficacy of (i) changes to behavioral patterns that do not involve building shell modifications; (ii) straightforward air-infiltration mitigation measures, and (iii) insulation measures. We derive estimates of net lifetime savings resulting from these measures, in terms of energy, carbon emissions and dollars. This study points out explicitly the importance of local and regional patterns in decision-making about what fraction of necessary regional or national emissions reduction might be accomplished through energy-efficiency measures and how much might need to concentrate more heavily on renewable or other carbon-free sources of energy.     

Modeling global residential sector energy demand for heating and air conditioning in the context of climate change

In this article, we assess the potential development of energy use for future residential heating and air conditioning in the context of climate change. In a reference scenario, global energy demand for heating is projected to increase until 2030 and then stabilize. In contrast, energy demand for air conditioning is projected to increase rapidly over the whole 2000–2100 period, mostly driven by income growth. The associated CO₂ emissions for both heating and cooling increase from 0.8 Gt C in 2000 to 2.2 Gt C in 2100, i.e. about 12% of total CO₂ emissions from energy use (the strongest increase occurs in Asia). The net effect of climate change on global energy use and emissions is relatively small as decreases in heating are compensated for by increases in cooling. However, impacts on heating and cooling individually are considerable in this scenario, with heating energy demand decreased by 34% worldwide by 2100 as a result of climate change, and air-conditioning energy demand increased by 72%. At the regional scale considerable impacts can be seen, particularly in South Asia, where energy demand for residential air conditioning could increase by around 50% due to climate change, compared with the situation without climate change.     

On the economics of hydrogen from renewable energy sources as an alternative fuel in transport sector in Austria

The core objective of this work is to analyse the possible future relevance of hydrogen from renewable energy sources in the transport sector from an economic point-of-view with special focus on Austria. The analysis is conducted in a dynamic framework until 2050.     

Quantifying the decrease of the photovoltaic panels’ energy yield due to phenomena of natural air pollution disposal

Photovoltaic (PV) applications, gaining worldwide interest during the last years, comprise a promising renewable energy based solution, able to considerably contribute to the constantly increasing energy demand of our planet. Currently, residential applications possess a considerable share of the global PV market since fiscal and practical incentives have reinforced their promotion. On the other hand, high population concentration, rapid industrialisation and economic development of urban areas all over the world have caused significant degradation of the urban air quality. In this context, the actual performance of five identical pairs of roof-top PV-panels, operating in the aggravated urban environment of Athens (from the atmospheric air pollution point of view), is currently evaluated. For this purpose, a series of systematic experimental measurements is conducted within a certain time period and the influence of different dust deposition densities on the energy yield and the economic performance of the small power station is estimated. According to the results obtained, the presence of dust considerably affects the PV-panels’ performance since even a relatively small dust deposition density (≈1 g/m²) may result in remarkable energy losses corresponding almost to 40 €/kW_p on an annual basis.     

Operational energy in the life cycle of residential dwellings: The experience of Spain and Colombia

Life Cycle Assessment (LCA) has been applied within the residential building sector of two buildings, one in each a developed (Spain) and a developing (Colombia) country. The main goal of this paper involves the environmental loads and also brings together the operational energy for activities during the operation phase such as HVAC, domestic hot water, electrical appliances, cooking and illumination. The present research compares two real scenarios: Situation 1, where 100% of the dwelling’s energy is supplied with electricity only and Situation 2, where dwellings can be operated with natural gas plus electricity.     

Will energy regulations in the Gulf States make buildings more comfortable – A scoping study of residential buildings

Building envelope impacts upon energy consumption and indoor environment. The relationship between envelope components and indoor environment has become increasingly important, especially with the new emphasis on visual comfort, thermal comfort and indoor air quality. This paper examines the interaction between occupant thermal comfort and envelope component regulations in the Gulf States. The country chosen for this study is the Kingdom of Bahrain, the smallest country in the Gulf region. Simulation results and comparative studies were employed to investigate the impact of the current envelope component regulations on the internal environment. The paper focuses on residential buildings and concludes that the envelope component regulations contribute positively to the internal thermal performance. Although these envelope components are not generally the primary elements that impact upon internal thermal comfort there are circumstances when the components become very warm and occupants positioned close to them will experience discomfort. This paper shows that the thermal insulation regulation makes a small impact on thermal comfort, whereas the window regulation, particularly glazing, is more influential and that for most window areas, solar impacts are generally large.     

Analysis of PV/wind potential in the Canadian residential sector through high‐resolution building energy simulation

Rising fuel prices and global warming are two major issues that concern people today. In this paper, the effect that the integration of the hybrid photovoltaic (PV)/wind‐turbine generation can have on conservation of energy and reduction of greenhouse gases (GHGs) has been studied. Base‐case energy demands were calculated using building energy simulation software and then the residential buildings were equipped with the PV/wind‐turbine electricity generation devices. The results show that the integration of those equipments can reduce both cost of fuel and GHG emissions to a fair amount. Copyright © 2008 John Wiley & Sons, Ltd.     

Parametric cost–benefit analysis for the installation of photovoltaic parks in the island of Cyprus

In this work a feasibility study is carried out in order to investigate whether the installation of large photovoltaic (PV) parks in Cyprus, in the absence of relevant feed-in tariff or other measures, is economically feasible. The study takes into account the available solar potential of the island of Cyprus as well as all available data concerning current renewable energy sources (RES) policy of the Cyprus Government and the current RES electricity purchasing tariff from Electricity Authority of Cyprus. In order to identify the least-cost feasible option for the installation of 1 MW PV park a parametric cost–benefit analysis is carried out by varying parameters such as PV park orientation, PV park capital investment, carbon dioxide emission trading system price, etc. For all above cases the electricity unit cost or benefit before tax, as well as after-tax cash flow, net present value, internal rate of return and payback period are calculated. The results indicate that capital expenditure of the PV park is a critical parameter for the viability of the project when no feed-in tariff is available.     

Economic potential of energy-efficient retrofitting in the Swiss residential building sector: The effects of policy instruments and energy price expectations

The aim of this paper is to analyse the profitability of energy-efficient retrofit investments in the Swiss residential building sector from the house owner's perspective. Different energy price expectations, policy instruments such as subsidies, income tax deduction and a carbon tax, as well as potential future cost degression of energy efficiency measures were taken into account. The discounted cash flow method was used for the investment analysis of different retrofit packages applied to a model building scheduled for renovation, i.e. a single-family house constructed between 1948 and 1975. The results show that present Swiss policy instruments push investments for energy-efficient retrofitting to profitability. Cost degression has a minor significance for investment profitability. However, the most relevant factor for the investment analysis is the expected energy price. Expecting a future fuel oil price at the level of 2005, efficiency investments are close to profitability even without policy support. If higher energy prices were expected, energy-efficient retrofitting would be an attractive investment opportunity.     

Incorporating cycling costs in generation dispatch program – an economic value stream for energy storage

Increased variable generation penetration without reinforcing the power grid with additional flexibility in the form of fast responding reserves necessitates existing conventional generation fleet to undergo cycling operations that are detrimental to its economics and lifespan. This paper presents a systematic methodology to estimate cycling costs related to the ancillary service and start‐up/shutdown operations of various generators. Production costing programs are performed in the Institute of Electrical and Electronics Engineers 24 bus reliability test system to quantify the cycling costs associated with system operation. Two methods are investigated to reduce system cycling costs, namely, incorporating the cycling cost components within the generation offers submitted to the dispatch programs and integration of bulk energy storage. Simulation results were also used to assess the potential of storage projects to earn economic incentive when additional cycling cost components are incorporated within generation offers. Copyright © 2014 John Wiley & Sons, Ltd.     

Comparison of neural network,conditional demand analysis,and engineering approaches for modeling end-use energy consumption in the residential sector

This paper investigates the use of conditional demand analysis (CDA) method to model the residential end-use energy consumption at the national level. There are several studies where CDA was used to model energy consumption at the regional level; however the CDA method had not been used to model residential energy consumption at the national level. The prediction performance and the ability to characterize the residential end-use energy consumption of the CDA model are compared with those of a neural network (NN) and an engineering based model developed earlier. The comparison of the predictions of the models indicates that CDA is capable of accurately predicting the energy consumption in the residential sector as well as the other two models. The effects of socio-economic factors are estimated using the NN and the CDA models, where possible. Due to the limited number of variables the CDA model can accommodate, its capability to evaluate these effects is found to be lower than the NN model.