Use intelligent design to drive energy efficiency for commercial buildings

Property owners, management firms and brokerages regularly face challenges in maintaining or increasing profits and maximising valuation. Energy is a significant expense that can represent a substantial area of opportunity. 

Property firms are in an enviable position as compared with other industries in regards to energy. Utility costs can exceed 30 per cent of a building's overall operating expenses, yet many organisations are not managing energy usages at all or are not fully leveraging all available opportunities.

To help property firms begin to benefit from an energy management program, engineers first need to educate their customers on how energy affects their business.

Like many operational expenses, energy and its associated financial opportunities can be considered in terms of three dimensions of costs: fixed, variable and exceptional. Specific information and functionality is required to take advantage of each one. Power monitoring systems cost-effectively address all three dimensions.

Energy costs are often allocated to tenants based on a common formula – normally based on the square footage of the tenant relative to the total leased space in a building. This can be highly inaccurate. Tenants increasingly ask to be more accurately billed, and if they question a bill, they would like to see supporting data. In some areas leases now include accurate sub metering as a standard clause. 

Power monitoring systems provide a complete sub metering solution that supports all forms of utilities (e.g., electricity, gas, water). Systems can leverage existing tenant meters while allowing new ones to be added where required.

Meter data is automatically uploaded on a frequent basis to the power monitoring system software over corporate networks, the Internet, or wireless communications, realising a low total cost of ownership while enabling limitless reach across all properties in a nationwide or worldwide portfolio.

Buildings include a variety of high-demand loads, including HVAC components like rooftop units, chillers and fans, as well as lighting systems. For a data centre or server operating within a commercial building, energy costs can be even higher, with up to 50 per cent of energy cost attributed to power and cooling of the data centre. 

In-house operations personnel or outsourced services periodically "tweak" a Building Automation System (BAS) to assure comfort based on some basic measured values and feedback from occupants. Maintenance of systems and components is typically based on estimates of equipment operation and on predefined service schedules.

These methods subject a property management firm to risk in terms of poor energy efficiency and potential equipment mis-operation or failure. Opportunities are often missed because energy-related information is often limited in both amount and accuracy.

Power monitoring systems deliver the intelligence and insight to effectively control energy assets.

Power monitoring systems deliver the intelligence and insight to effectively control energy assets.

Though often considered a building's energy management system, a BAS is primarily designed to react to set conditions, not to deliver the breadth or accuracy of data and analysis required to effectively control energy costs.

In contrast, power monitoring systems automatically collect and report detailed power and energy information from all energy assets, including HVAC, BAS, electrical distribution systems and onsite generators. Such a system continuously tracks conditions and alerts operations staff to any potential problems before they occur.

The source can then be quickly isolated using graphical facility overviews of real-time electrical and equipment status, historical information, and "drill-down" analysis. These tools help drive proactive maintenance, extend equipment life, avoid capital costs and reduce labour.

Power monitoring systems also deliver the information corporate and facility managers need to deal with energy in financial terms. Browser-based "dashboards" listing key performance indicators (KPIs) help track and verify enterprise- wide conditions and costs on a dynamic basis.

Energy consumption for buildings and other cost centres can be easily aggregated and normalised to remove independent variables such as temperature or square footage from the profile. This allows for accurate direct comparison, helping identify inefficiencies and opportunities to reduce usage.

For example, start-up procedures can be optimised to avoid demand peaks, HVAC settings can be adjusted to reflect occupancy and weather patterns, or elevator timing might be modified to reduce consumption.

The power monitoring system will also provide an accurate energy baseline prior to any retrofit or initiative to help verify effectiveness afterward. Ultimately, building performance can be benchmarked and the information used to support certification rating systems such as those developed by the Green Building Council Australia.

Billing errors from a utility or other energy provider can be another area of concern. Errors that benefit the building (i.e. under-billing) can be as problematic as those that are in the utility's favour, as most supply contracts allow the utility to recover these missed charges months or years after the error occurred. 

To help avoid these situations, power monitoring systems can be equipped with utility-class "shadow meters" installed in parallel with the utility's billing meters at the service entrance to each facility. The power monitoring software calculates an accurate bill, matching the utility's rate structures, and compares each billing period to the utility's bill to identify any inconsistencies.

The electrical systems and other energy distribution systems for new facilities are often over-designed, and additional capacity in existing buildings goes undiscovered due to a lack of information about energy consumption characteristics.

A power monitoring system delivers detailed load profiles for each building and major circuit, helping planners ensure the use of existing capacity is safely maximised to avoid unnecessary upgrades. Accurate data on existing facilities helps simplify the estimation of future expansion needs and ensures infrastructure for new buildings is "right-sized" to minimise costs.

The source of reliability problems can sometimes be on the utility side of a facility's service entrance; for example, lightning causing massive power spikes on transmission lines that then propagates through to the customer. To guard against external sources, companies will often install filtering devices.

A facility can also switch to UPS systems or backup generators in the event of major outage. These techniques will only be effective if equipment is continuously tested and optimised to ensure dependability. Power monitoring systems help engineers evaluate how the overall quality of power is impacting equipment and uptime.

Power monitoring systems can help to ensure energy investments realise maximum payback.

Power monitoring systems can help to ensure energy investments realise maximum payback. 

Permanently installed intelligent meters monitor key distribution points and upload real-time data and event logs to visualisation software that helps personnel analyse conditions, isolate the source of disturbances or failures, predict future occurrences, and validate the proper operation of all mitigation equipment during a critical event.

Computers and data processing equipment, motors, power switching or protection devices, and even equipment designed to mitigate some power problems can all add unwanted harmonic frequencies and high-voltage transients onto a facility's electrical distribution network.

These, in turn, can cause data loss and malfunctions in computers, building automation systems, or process equipment. Worse, transformers and conductors can overheat and fail or power breakers can trip needlessly, any of which can cause a complete facility outage.

Using phone or workstation, a power monitoring system will alert personnel to imminent problems, help them isolate and analyse high-risk conditions, and perform the necessary control functions to avoid downtime and the associated lost revenues.

Capital replacement costs can be avoided or deferred and workload for maintenance staff reduced. Being able to guarantee higher reliability can also help keep existing tenants satisfied and attract businesses that are especially sensitive to power quality glitches.

Power monitoring systems can help to dynamically identify and respond to opportunities, drive best practices, and provide the essential follow-up that ensures energy investments realise maximum payback. From automated bill checking to improved procurement, operational efficiencies, and power reliability, power monitoring technology offers the key to extracting true financial and competitive advantages from energy.

[Samuel Coupel is Product Manager, Energy Management & Power Quality, Schneider Electric Australia.]

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