Water Performance Benchmarks for New Zealand: Understanding Water Consumption in Commercial Office Buildings

<p>There is an increasing amount of literature outlining the issues underlying water shortages and restrictions to come in most regions of New Zealand. The problem is not helped by rising demands and climatic changes, as well as both a lack of measured data, and a lack of any demand-side incentives. No attempt has been made to assess how the users of commercial buildings are consuming potable water. There are no benchmarks for water performance in buildings, hindering attempts to improve water efficiency. This study investigated the water use in 93 Auckland and Wellington commercial office buildings. The data collected from both survey level water audits (on-site investigations, historic billing analysis) and full water audits (water monitoring), were used to develop market-based water performance benchmarks, and a Water Efficiency Rating Tool (WERT). This was done to understand water consumption in these buildings, and to determine the feasibility of using performance based data for the development of a water benchmarking system. The principal results were in the form of both a benchmarking index system, and the WERT. The benchmarking study found that Net Lettable Area (NLA) was the most statistically and pragmatically appropriate driver for water use. lt also found that, due to the distinct difference in tariff structures and incentives between Auckland and Wellington, different benchmarks for the two regions (Auckland 'Typical' use 0.76m³ / m² / year, and Wellington 'Typical' use 1.03m³ / m² / year) were required. The WERT calculates a building Water Use Index (WUI- m³ / m² / year) , estimates its end-use disaggregation, and provides recommendations through outlining the financial viability of implementing specific water efficiency measures. This tool utilised six design criteria to ensure target market usability: accuracy (demonstrated at ±8. 5%) ; relevance and realism; practicality; promotion of understanding and action; objectivity; and effective communication. Further recommendations included satisfying some of the many knowledge gaps present in the New Zealand water industry concerning office building water use. These included: introducing a national legislative or standard document providing guidelines on demand-side management of water; investigation into changing tariff structures to include a volumetric charge for all building types to increase individual awareness and education of water use; research into the durability of water meters; and expanding the research to include other New Zealand regions.</p>

Water Performance Benchmarks for New Zealand: Understanding Water Consumption in Commercial Office Buildings

<p>There is an increasing amount of literature outlining the issues underlying water shortages and restrictions to come in most regions of New Zealand. The problem is not helped by rising demands and climatic changes, as well as both a lack of measured data, and a lack of any demand-side incentives. No attempt has been made to assess how the users of commercial buildings are consuming potable water. There are no benchmarks for water performance in buildings, hindering attempts to improve water efficiency. This study investigated the water use in 93 Auckland and Wellington commercial office buildings. The data collected from both survey level water audits (on-site investigations, historic billing analysis) and full water audits (water monitoring), were used to develop market-based water performance benchmarks, and a Water Efficiency Rating Tool (WERT). This was done to understand water consumption in these buildings, and to determine the feasibility of using performance based data for the development of a water benchmarking system. The principal results were in the form of both a benchmarking index system, and the WERT. The benchmarking study found that Net Lettable Area (NLA) was the most statistically and pragmatically appropriate driver for water use. lt also found that, due to the distinct difference in tariff structures and incentives between Auckland and Wellington, different benchmarks for the two regions (Auckland 'Typical' use 0.76m³ / m² / year, and Wellington 'Typical' use 1.03m³ / m² / year) were required. The WERT calculates a building Water Use Index (WUI- m³ / m² / year) , estimates its end-use disaggregation, and provides recommendations through outlining the financial viability of implementing specific water efficiency measures. This tool utilised six design criteria to ensure target market usability: accuracy (demonstrated at ±8. 5%) ; relevance and realism; practicality; promotion of understanding and action; objectivity; and effective communication. Further recommendations included satisfying some of the many knowledge gaps present in the New Zealand water industry concerning office building water use. These included: introducing a national legislative or standard document providing guidelines on demand-side management of water; investigation into changing tariff structures to include a volumetric charge for all building types to increase individual awareness and education of water use; research into the durability of water meters; and expanding the research to include other New Zealand regions.</p>

Implications of Water Tariff Structures on Water Demand in Santa Cruz Island (Galapagos Archipelago)

The island of Santa Cruz, located in the Galápagos Archipelago has experienced a significant increase in tourism with consequent growth of the local population over the past two decades. The rapid increase in the number of hotels and restaurants raised pressure on the water demand needed to satisfy the customers’ needs. The municipality of Santa Cruz has not been capable of coping with current expansion rates in order to provide good quality water services. Financial constraints, limited personnel, and tariff structures are the main reasons that restrict the capacity of the Department of Potable Water and Sanitation (DPWS) to manage the water supply system. There are two main settlements on the island are Puerto Ayora and its suburb, Bellavista, with a total population of approximately 14,500 and independent water supply systems. Puerto Ayora has a fixed-priced tariff per month, for categories established by the municipality. On the other hand, Bellavista has a metered system, with fixed consumer costs Yet, approximately 32% of water meters are faulty. Consequently, water demand in these two settlements varies significantly, which is likely influenced by the difference in tariff structures. This manuscript assesses the difference in tariffs between the two settlements. Furthermore, the impacts on revenues due to faulty meters (Bellavista) and fixed tariffs (Puerto Ayora) are quantified. In addition, several scenarios have been developed and analyzed in order to examine the benefits. Finally, the information regarding overdue bills and willingness to pay by the different categories of users has been examined. Results show that the revenues from water supply vary extensively between the two settlements. Due to the fixed tariffs in Puerto Ayora, the estimated cost per cubic meter of water varies depending on the specific category and estimated quantities of water used. In the case of Bellavista, water meters should be managed better and have regular maintenance. The high percentage of faulty meters gives an extra deficit to the municipality.

Techno-Economic Modelling of Micro-Hydropower Mini-Grids in Nepal to Improve Financial Sustainability and Enable Electric Cooking

In rural Nepal, micro-hydropower plant mini-grids provide renewable electricity to thousands of communities but the plants often have poor financial sustainability. Widespread uptake of electric cooking in such communities is currently not feasible due to high peak loads and limited capacity. In this paper, we develop a Remote-Areas Multi-Energy Systems Load Profiles (RAMP)-based stochastic techno-economic model for evaluating the economic viability of off-grid communities and improving their financial sustainability by introducing new appliances, productive end uses, and demand-side management measures. The model can be used to understand community electricity demand, assess economic status, determine equitable and profitable tariff structures, and plan new connections including electric cooking promotion or new industrial machines. Detailed electric cooking load modelling functionality was developed to represent Nepali cooking practices, scalable to approximate widespread uptake of electric cooking, and adaptable to other cookers and contexts. The model showed that a payment structure based on electricity consumption rather than a flat tariff could increase the income of a case study community in Eastern Nepal by 400%, although increased monthly payments for certain households from NPR 110 (USD 0.93) to NPR 500–1100 (USD 4.22–9.29) could present difficulty. However, households could reduce their electricity consumption and a more equitable tariff structure could be chosen while preserving plant profitability. The number of industrial machines such as mills could be doubled and up to 40 households provided with electric cookers if demand-side management measures were introduced.

Opening Up Transactive Systems: Introducing TESS and Specification in a Field Deployment

Transactive energy systems (TS) use automated device bidding to access (residential) demand flexibility and coordinate supply and demand on the distribution system level through market processes. In this work, we present TESS, a modularized platform for the implementation of TS, which enables the deployment of adjusted market mechanisms, economic bidding, and the potential entry of third parties. TESS thereby opens up current integrated closed-system TS, allows for the better adaptation of TS to power systems with high shares of renewable energies, and lays the foundations for a smart grid with a variety of stakeholders. Furthermore, despite positive experiences in various pilot projects, one hurdle in introducing TS is their integration with existing tariff structures and (legal) requirements. In this paper, we therefore describe TESS as we have modified it for a field implementation within the service territory of Holy Cross Energy in Colorado. Importantly, our specification addresses challenges of implementing TS in existing electric retail systems, for instance, the design of bidding strategies when a (non-transactive) tariff system is already in place. We conclude with a general discussion of the challenges associated with “brownfield” implementation of TS, such as incentive problems of baseline approaches or long-term efficiency.

Do Households Respond to the Marginal or Average Price of Piped Water Services?

Water utilities commonly use complex, nonlinear tariff structures to balance multiple tariff objectives. When these tariffs change, how will customers respond? Do customers respond to the marginal volumetric prices embedded in each block, or do they respond to an average price? Because empirical demand estimation relies heavily on the answer to this question, it has been discussed in the water, electricity, and tax literatures for over 50 years. To optimize water consumption in an economically rational way, consumers must have knowledge of the tariff structure and their consumption. The former is challenging because of nonlinear tariffs and inadequate tariff information provided on bills; the latter is challenging because consumption is observed only once and with a lag (at the end of the period of consumption). A large number of empirical studies show that, when asked, consumers have poor knowledge about tariff structures, marginal prices, and (often) their water consumption. Several studies since 2010 have used methods with cleaner causal identification, namely regression discontinuity approaches that exploit natural experiments across changes in kinks in the tariff structure, changes in utility service area borders, changes in billing periods, or a combination. Three studies found clear evidence that consumers respond to average volumetric price. Two studies found evidence that consumers react to marginal prices, although in both studies the change in price may have been especially salient. One study did not explicitly rule out an average price response. Only one study examined responsiveness to average total price, which includes the fixed, nonvolumetric component of the bill. There are five messages for water professionals. First, inattention to complex tariff schedules and marginal prices should not be confused with inattention to all prices: customers do react to changes in prices, and prices should remain an important tool for managing scarcity and increasing economic efficiency. Second, there is substantial evidence that most customers do not understand complex tariffs and likely do not respond to changes in marginal price. Third, most studies have failed to clearly distinguish between average total price and average volumetric price, highlighting the importance of fixed charges in consumer perception. Fourth, evidence as of late 2020 pointed toward consumers’ responding to average volumetric price, but it may be that this simply better approximates average total price than marginal or expected marginal prices; no studies have explicitly tested this. Finally, although information treatments can likely increase customers’ understanding of complex tariffs (and hence marginal price), it is likely a better use of resources to simplify tariffs and pair increased volumetric charges with enhanced customer assistance programs to help poor customers, rather than relying on increasing block tariffs.

In Pursuit of Sustainable Mobile Policy: A Study of Consumer Tariff Preferences under Uncertainty

Literature suggests that consumers expect disutility not only from payment uncertainties but also from reference uncertainties embedded in mobile plans. This paper develops a model of mobile plan choice incorporating both reference and payment uncertainties and uses this model to derive testable implications. The paper argues that consumer choice reflects those uncertainties more than could be justified by rational choice theory. Such patterns, the paper hypothesizes, would be more salient in the choice of data plan than voice plan because consumers tend to perceive data usage to be less controllable than voice usage, thus preferring the plan that reduces uncertainty. The paper tests the predictions with data from a laboratory study analyzing a series of choices between plans with different tariff structures—flat-rate, two-part, and three-part tariffs. As predicted, the results suggest that payment and reference uncertainties create significant disutility for consumers, especially when they perceive high uncertainty about their usage. Such understanding of consumer preference and underlying psychological biases is important in the sense that it provides an essential basis for the development of sustainable mobile policy.