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Measure, Ensure

The final challenge to an energy and water conservation programme is the measurement and verification of the accrued savings

| | Mar 15, 2010 | 2:33 pm
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The final challenge to an energy and water conservation programme is the measurement and verification of the accrued savings

The real-estate industry is quite familiar with the concept of energy and water conservation. Many from this industry have either heard of the terminologies or been party to an energy audit. However, one of the fundamental challenges faced by many is, “How do I go about executing a professional and measurable energy and water conservation programme that can be presented to our management?” Another severe challenge faced by other energy conservation enthusiasts (and this is particularly true of many facility managers) is, “I have taken several measures to conserve energy and water, but I do not know how to measure the effectiveness of my initiatives and, therefore, have no results to report to management.” Between these two challenges lies the third challenge: “I need to float an RFP for selecting an appropriate vendor, but I do not know how to prepare one.”

When I was doing my engineering programme in energy engineering at the Indian Institute of Technology (IIT), faculty would not prepare us for these real-life project situations. Yes, we did become experts in energy modelling and theoretical energy auditing, but when I started my professional career, I realised that there is more to it than just calculating specific energy consumptions. For example, while it is easy to draw up a Sankey diagram during an exam when the basic information is provided, in real-life projects the situation is altogether different, because data collection itself is a major challenge. Fourteen years of working in the field of energy and water conservation has helped me learn some of the better approaches to planning, initiating, executing, monitoring, controlling and closing out effective energy- and water-conservation projects, particularly in this region.

WHERE TO START

Different people initiate energy- and waterconservation programmes at different stages of a project, with varied levels of intensity and depth of knowledge. In order to eliminate a well intentioned yet confused approach, I would personally recommend to start with an initial assessment of where your organisation stands currently in the overall scheme of savings, by using the “Energy Management Matrix” based on the Building Research & Energy Conservation Support Unit’s 1993 Energy Management Matrix:

Let us look at a few typical examples, which many readers may be able to identify with:

1.) A shopping complex or a commercial office building. The usual practice in such facilities is that either the energy and water costs are pre-estimated and included into the leasing rates or while the individual shops/ offices are metered for direct energy consumption, the AC bill is distributed amongst the tenants every month on a prorata basis depending on the square footage occupied and common area. In a situation like this, there is rarely any explicit energy conservation policy or energy manager with a formal delegation of responsibility for energy consumption. There is no contact with users other than monthly billing. However, the accounting department within such facilities would maintain dedicated invoice data for billing purposes, although there will be no accounting for energy consumption, no promotion of energy efficiency and definitely no investment in increasing energy efficiency in the premises. A very customary indicator of such a situation would be a noticeably cold indoor environment, high levels of lighting and numerous halogen lamps. For facilities like these, the energy management matrix would look somewhat as below:

2.) A four- or a five-star hotel. From my professional experience, I have found four- or five-star hotels to be extremely energy conscious. Although this sector is one of the highest consumers of energy, water and gas, from within the building sector, they are also the most conscious of their utility costs.

The responsibility of tracking and essentially keeping utility consumptions under control, although perhaps not necessarily actively managing utilities always, rests squarely on the shoulder of the chief engineer and his engineering team. A familiar sight, either inside or outside the chief engineer’s office, is daily tracking of utility consumptions.

Standard analysis is carried out by the engineering team on a daily basis, in conjunction with the occupancy rates and in comparison with expected daily consumptions. Any variation is, indeed, investigated and corrective action implemented. Such facilities would rate as following on the BRECSU matrix:

While the first example demonstrates a balanced matrix, it is clearly balanced at the wrong end of the maturity level. The second example, although may not be balanced, largely reflects an organisation or a facility that is conscious of its utility costs, and takes action on a regular basis to make sure that the utility bills are strictly under control, to the extent possible.

Likewise, utilising the BRECSU Energy Management Matrix, it would be relatively straightforward to ascertain the maturity level of any organisation or a facility in the context of energy and water conservation. This should typically be the first step for any organisation intending to implement an energyand water-conservation programme effectively.

While the interpretation of some of the criteria might get ambiguous, it is always preferable to have a healthy introspection and, possibly, even err on the side of pessimism. This gives rise to the opportunity to excel quickly through an effective implementation of the programme.

ENERGY & WATER CONSERVATION PROGRAMMES

Typically, conservation programmes can be executed at either of two phases within the life-cycle of a facility: (a) Design Phase or (b) Operation and Maintenance Phase.

There is, of course, a potential third phase where a conservation programme can be significantly effective and both financially and technically feasible. For instance, renovating old facilities or upgrading outdated electromechanical systems provides a golden opportunity to implement a full-fledged energy efficiency programme, including a green office certification like the TECOM Management Office Renovation, which is a LEED Platinum project.

However, although this is a unique phase in the life-cycle and brings with it its own pros and cons (potentially subject for a different treatise), for the sake of simplicity, it can be clubbed together with the design stage. A design stage conservation programme is carried out, as the name suggests, when a facility is being designed. This offers several key advantages that may not be achievable when the same exercise is conducted when a facility is already in the operational stage.

The first and foremost amongst this is the financial feasibility of several critical measures that otherwise would not have an acceptable ROI, such as connecting an HVAC condensate to the irrigation tank or installing LED lights instead of halogens and several others.

Even with regular conservation measures that have a payback period of two years or less, if implemented at the design stage, the same payback period can be reduced to less than six months. This is due to the offset in capital expenditure that would have otherwise been incurred for standard design. The bigger financial benefit perhaps stems from the fact that a design stage conservation programme may end up downsizing or correct sizing installed equipment, especially when ASHRAE 90.1-2004 design parameters are applied.

I have LEED-supervised a project where the peak HVAC tonnage required went down to 1,550 TR at the final design stage from 2,500 TR at the preliminary design stage, through the adoption of ASHRAE 90.1-2004 design criteria. Renewable energy projects, with solar photovoltaic projects in particular, can become financially attractive when adopted at the design stage of a facility. A case-in point is the solar photovoltaic car park lighting at the Dubai Outsource Zone where the net capex for the project was reduced to only $6,262 (Dh23,000), since the project was not a replacement of existing lights, but rather an alternative.

A design stage project has the added advantage of a much easier green building certification as an enhancement of a simple energy and water conservation programme. In fact, this opportunity is quite harmonised, so much so that we use the green building certification as the broader framework for indulging in energy and water conservation as well.

The result is not only a resource-efficient facility, but also one that is officially certified. As an added benefit, the certification process and its requirements provide a framework for a developer to measure the design performance of the facility. Additionally, if a facility management assessment is also included into the energy and water audit at the design stage, future O&M problems and the costs associated with resolving these, can be easily avoided.

The biggest challenge of a design-stage utility assessment occurs in the fact that savings estimation remains a theoretical exercise, and one has to rely on energy modelling software, which can only be accurate in the long run if all assumptions in relation to operating hours and weather conditions were to be strictly as per modelling inputs. This unfortunately is rarely the case.

Compared to this, an energy- and waterconservation programme in an existing facility is a far more “tangible” engineering project, although not necessarily from the finance manager’s point of view. At least, such a programme would require the physical changing of light bulbs, installation of VFDs etc. Fundamentally, such a programme is always dictated by an ROI which, although may vary from organisation to organisation, has in general been fixed at two years as acceptable in this region.

Such a programme also provides great opportunity to upgrade Building Management Systems and MEP equipment, especially when critical upgrades are required but cannot be budgeted for (bottom of the food chain syndrome). The performance of such a programme is easily measurable by virtue of simply comparing past and present utility bills (at the very minimum, with more complex scientific methodologies available if necessary). Sometimes, such a project can be substituted by a building re-commissioning exercise, which more often than not could lead to an energy reduction of up to 10%.

Finally, it has been observed in most of the projects, which I have executed that indoor environmental quality actually improves due to the implementation of an effective energy conservation programme. In the TECOM Management Office renovation project, lighting levels went up by 75%, although lighting energy consumption came down by more than 50%. Design-stage energy and water conservation programme is much more effective than when a facility is already functional, owing to easier implementation and improved ROI (if not actual reduction in Capex) for conservation measures.

ENERGY and WATER-CONSERVATION MEASURES

An energy and water-conservation programme focuses purely on the wastage and inefficiencies in the energy and water consumption systems or processes, and explores how to optimise the same, thereby resulting in reduction in utility consumption. Fundamentally, if there is no wastage, there is no opportunity to save.

An energy and water-conservation programme cannot and should not compromise on comfort conditions. Comfort conditions are set out by engineers through standards like ASHRAE 90.1-2004, ASHRAE 62.1-2004 etc. These standards may be further fine-tuned to suit individual needs, as building occupants may have varying personal levels of comfort, but only at the operation phase. This is applicable for buildings. For industries, the programme should not negatively impact on production.

There are three broad areas that one must address in order to implement an energy and water conservation programme effectively:
(a) The identification of energy- and waterconservation measures;
(b) Implementing such a programme and
(c) The measurement and verification of savings.

The identification of energy and water conservation measures is usually done through an energy audit. This audit essentially attempts to identify where the wastages/inefficiencies in a system lie, and then tries to eliminate these through a variety of solutions. These wastages are caused by a variety of reasons (all of which can be identified and redeemed), such as over-design.

Let us illustrate this through three case studies. Let’s start with Dubiotech HQ building, which was one of the first projects to pursue LEED certification at TECOM Investments. At the conclusion of the preliminary design stage, the project was estimated to require about 2,500 TR of air-conditioning capacity. By applying ASHRAE 90.1-2004 design parameters, the air-conditioning requirement was brought down to 1,550 TR. While this tonnage optimisation is not strictly required for LEED certification, this exercise undertaken by the Sustainable Energy and Environment Division (SEED) of TECOM clearly showcases the scale of opportunity that lies in right-sizing a facility.

Now, such an exercise not only optimises operating energy requirements, but also drastically cuts down on the demand charges to be paid by the facility to the district cooling service provider, which in turn benefits from the opportunity to right-size his plant capacity.

Eliminating over-design using LEED as a tool – while the debate still rages on both for and against LEED, I have found it to be a useful tool/ mechanism which we have successfully utilised to drive our costs down in several projects. Since LEED mandates certain flow rates and techniques to reduce potable water consumption, applying the LEED guidelines in the design of our new projects, as well as retrofitting our existing wash basins, has dramatically stopped us from over-designing our water systems. The following chart showcases our water performance at the Dubai International Academic City’s Phase 3 facility (LEED Silver):

Over Design

Over Design in an existing building – this is a classic case study of a 600,000-square-foot (sq ft) mixed-use complex where I had executed an energyconservation programme through performance contracting. As a first step, before conducting a detailed energy audit, the operations of the electromechanical systems were optimised through the building management system. Appropriate time-scheduling and set point scheduling were programmed, based on the usage pattern of the facility.

This exercise alone resulted in a 15% energy savings, although the occupancy went up by 130,000 sq ft (reaching 90%). While this is a satisfactory performance for an energy conservation programme that did not need any investments, a bigger achievement was that, during peak summer conditions, the facility needed only three (out of the installed 10 chillers) to operate in order to achieve the design comfort conditions.

In effect, the facility was operating on 1,260 TR of peak HVAC against an installed capacity of 3,800 TR. If an energy assessment had been conducted at the design stage, the project would have easily saved approximately $816,771 (Dh3m) in avoided Capex.

Lack of Controls

This is a typical problem in office complexes, and I have yet to come across a facility which does not suffer from a lack of adequate and appropriate controls. Possible exceptions would be (a) offices where thought has been given to this issue during the design stage; (b) offices where this was such a critical problem that retrofit has been carried out to resolve this or (c) offices that have been LEED certified.

The lack of controls issues sometimes can be congruent with over-design, such as a large number of lights in an open plan office but only one switch to operate them. Another classic example of lack of controls in this region is deficit of operable windows even in low-rise office blocks, without which occupants have to keep operating their expensive HVAC equipment even during the coldest winter days. The SEED office at Dubai Knowledge Village has operable windows on three facades and, for more than two months in winter, the air-conditioning equipment is not operated since the office is naturally ventilated.

Inappropriate Usage

Sometimes even though the right technology is used, the application of it could be inappropriate. Installing metal halide lamps inside commercial offices is one such example, although one must admit that it is not so widely prevalent. While metal halides can be enormously efficient compared to other light sources, they do generate significantly high amounts of heat and glare.

While it may be a good idea to have large amount of glazing in buildings, since the glass area is not shaded, occupants can be habitually seen to be drawing the curtains down to block the outside glare and switch on artificial lighting – in daytime! A simple measure like shading the glass area would not only eliminate the sunlight from impinging inside a facility, but would also allow the daylight to come in and thereby eliminate the need for artificial lighting. Imagine putting all the glazing for the view and unable to enjoy it due to the curtains.

Outdated Technology

A peculiar fascination for halogen spotlights, installing Building Management Systems that do anything but manage the facilities’ electromechanical equipment and using thermostats that do not have signage for temperatures are several examples of outdated technology still being used quite commonly.

In 2008, SEED implemented the halogen phase-out project at the Business Centre of Dubai Media City wherein close to 1,000 halogen spotlights were replaced with a combination of LED and CFLs. A snapshot of this project is given below:

The additional benefits are the following: with improved air-conditioning due to cooler lamps, occupants do not feel as hot anymore; more uniform lighting – alternate bright and dark spots are eliminated; lower maintenance cost due to longer life of energy efficient lamps (LED lamps can last more than 10 years) and improved indoor environmental quality with no hotspots.

Human Behaviour

Although I have listed this parameter as the last, it is to my mind the most important of all and, if not addressed at the very initiation, has the potential to ensure the failure of an energy and water conservation programme. SEED has utilised several techniques and approaches to sensitise building occupants. These include developing an in-house awareness programme for employees on the issue of climate change, switch-me-off stickers, table totems and stickers for washrooms.

PERFORMANCE CONTRACTING

While many organisations do end up doing one thing or the other as per the BRECSU energy management matrix, most facility operators find it extremely challenging to initiate, plan, execute, monitor and close out a comprehensive energy- and water-conservation programme.

There are several reasons for this: in most organisations, energy- and waterconservation initiatives end up becoming the part-time responsibility of the facility manager or not at all; in some facilities, even after a person is assigned responsibility for this function, it is not reflected in his/her performance objectives; even when it is included in the performance objective, a budget is rarely allocated for this activity.

This is a typical ‘responsibility without authority’ situation and very commonplace in the industry on energy and water conservation issue. In the worst situation, budgets are not even allocated for regular planned preventive maintenance and upgrade works.

The best situation I have personally come across is an organisation with a dedicated division/team of qualified personnel with the responsibility to define and implement a comprehensive energy and water conservation programme; budgets are hard to come by, however, especially in times of a recession.

In such situations, the best way to implement an energy and water conservation programme effectively is to first optimise the operation of the facility’s electromechanical equipment. This does not require any Capex. Having implemented this, it is best advised that the facility engage in a “Performance Contract” mechanism. This is a means of raising money for investments in energy efficiency that is based on future savings. It enables money that will be saved as a result of the introduction of a new energyefficient technology to be used to offset the cost of financing, installing and operating that technology.

In this arrangement, the facility owner does not have to incur any upfront Capex or absorb any risk of failure. An energy service company (ESCO), specialising in the business of energy and water conservation, can be engaged to audit a facility, identify equipment/strategies required to reduce energy and water consumptions (without negatively affecting comfort conditions or production), invest the Capex required to purchase such equipment and install and manage the entire project.

Such a service is typically provided by three different types of entities:

Equipment Suppliers. Performance contracting services are normally offered by an independent branch of companies, such as industrial control manufacturers, both as a marketing strategy and as an additional revenue source. This is the best option if these technologies are the main measure being considered.

Fee-Based Service Companies. Performance contracting is the only service offered by these companies, which grew out of energy management and other contractors. They are the best choice if a wider range of measures is being planned, or if the contract is to cover building renovation and longterm facilities management.

Utility-Based ESCOs. Some electric utilities have set up their own ESCOs to deliver demand side management programmes, and to provide an additional source of revenue. These are a good choice if the project is focused on electricity or gas technologies, although this is not a prevalent concept in this region.

M&V OF SAVING

The final challenge to an energy- and waterconservation programme is the measurement and verification (M&V) of the accrued savings. We need to verify savings because energy and water savings are dependent on various factors, such as weather, occupancy, added load, disconnected load and operating hours, among other things.

Therefore, while installing a VFD on a FAHU should generate savings, the HVAC energy consumption might increase, because the weather in a particular month was warmer compared to the weather in the corresponding month during the year prior to the installation of the VFD. This exercise can range from being very simplistic to ending up being very debatable when more and more parameters start getting involved.

Ultimately, the level of complexity will depend on the agreement between the facility owner and the service provider as to how many parameters need to be included in the M&V process. Verifying that savings actually occur is an important part of any performance contract. The couple of methods normally used are the following:

Savings based on utility bills. These provide the most common method used for savings verification. Here, energy and water savings provide the basis for repayments. Baseline consumption is determined using past energy bills. Savings are calculated using the actual energy bills received throughout the contract period.

Measured savings. These involve ‘before’ and ‘after’ measurement of utility use by the technologies installed in the project. This is the most exact method of determining savings, but also the most costly. Adjustments have to be made for weather and facility use changes, and because equipment loads can vary from day to day, elaborate protocols need to be established.

International Performance Measurement and Verification Protocol (IPMVP) has been widely used as the technical basis for determining energy savings in building retrofit projects. Introduced in 1994 as the North American Energy Measurement & Verification Protocol (NEMVP), IPMVP has become the industry standard. International use of NEMVP led to development of an international protocol in 1997.

A standard performance contract for energy and water conservation between a facility owner and a service provider does not strictly need to follow the strong scientific approaches of IPMVP. For the purposes of green building certification, however, the adoption of this protocol may become necessary. There are four different options of measuring and verifying energy savings under the IPMVP:

The chart, above, exhibits the M&V of the Energy Conservation Programme at TECOM Investments using IPMVP Option C. Since this is an in-house project being implemented by SEED in existing facilities, the only adjustment that is made in the measurement of energy savings is the weather related adjustment, carried out on the basis of differentials in ‘cooling degree days’ every month.

As will be noted from the below chart tracking the water conservation programme at TECOM Investments, and again since this is an in-house project, there are no adjustments made in the water savings calculations. The saving is the simple difference between the water consumption before and after implementation of the conservation measures, and complies with IPMVP Option C. Again, this can be easily done because the facilities are all present, and the historical data are available. No adjustments are made as it is not a priority issue at the moment.

The M&V mechanism becomes slightly trickier in the case of design stage energy conservation programme, especially when a project is pursuing a green building certification. In existing buildings, the performance of a conservation programme can always be measured and verified through a basic comparison of metered utility consumptions, before and after the implementation of the conservation measures.

When a facility is being designed, the only option available is to carry out an energy modelling exercise, which will, through the use of specialised software, predict more or less accurately the future energy consumption of the facility in design. One of several widely used kinds of software is the Visual DOE, which, although quite basic, can predict future energy consumptions to acceptable levels of accuracy. The energy modelling software also allows the opportunity to evaluate the cost-benefit analysis of several energy conservation measures. This methodology is compliant with IPMVP Option D.

The LEED Silver Dubai International Academic City Phase 3 was the second LEED certified project at TECOM Investments and the fifth in the Gulf Co-operation Council bloc. Some of the energy conservation measures adopted in the project included the following: HVAC load optimisation; enhanced levels of building envelope insulation; heat recovery wheels; limited glazing in building envelope; zero use of halogen lamps in common areas; energy efficient light bulbs and significantly low lighting power densities.

In order to quantify the savings that can be expected from these measures, a Visual DOE energy modelling exercise was conducted, and the following chart shows the estimated savings expected from the various sectors of energy consumers.

Overall, the facility is designed to be 21.7% more energy-efficient which translates to $260,545 (Dh956,984) per year as per the energy model.

RECOMMENDATIONS

Irrespective of the size of your facility, it is always a good idea to have an ongoing energy and water conservation programme in place. In fact, the bigger the organisation, the better the financial benefits. For old facilities, the savings from an energy and water conservation programme can throw up much needed cash for system upgrades. It is always a good idea to set up your own in-house expertise if you have a large amount of building stock.

The investment in such a team will pay back for itself in a matter of months/ weeks. For up-scaling your ambition on the initiatives, it would be best to engage a professionally qualified service provider. As I mentioned at the Cityscape Dubai 2009 panel discussion on “From the Red to the Black via the Green”, sustainable development initiatives through its main pillar of energy and water conservation can easily resuscitate the P&L, or profit and loss statement, of any organisation.


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