Is your BMS the answer to the energy crisis?

BMS the cure or curse?

Annual Energy Costs Before, and then After new BMS installation

There is a school of thought, in the race for low carbon, lower energy consumption, etc. that installing a new BMS (building management system) will magically solve all your energy problems.  A quick review of the above chart gives the hard evidence, it failed, and it is difficult to believe that more building owners don’t demand evidence from vendors, after installation, to support those glossy brochures.

In my experience, vendors sell sell sell, install, and move on to the next project, but where is the Measurement and Verification (M&V)? What is M&V? It is the name given to process,  that will essentially prove or disprove that those promised energy savings were achieved.

Generally, little post installation checking is conducted to try and validate the promised savings were achieved, whereas in reality the results are poor. In the above example, the peak month energy consumption actually increased by approx. HKD 90,000, hardly the savings often touted in the brochures.

BMS chiller operation

Central Chiller Plant Hunting – poor operation hurts energy consumption

Fortunately, whilst conducting energy audits I have access to the raw data, and plot charts like the above, and find a new BMS alone not the best choice for energy management.

Whether you choose a BMS, variable speed drives, or other means, you should pay the extra to monitor and report the results – trust but verify!  Properly commissioned installations can help monitor operating costs, but that is not the answer to improving energy efficiency.

 

Energy Audit – its not just about the lux

It is not just about the recording lighting level (known as LUX)

lighting energy audit

Lighting efficacy – Energy audits for buildings, typically include a lighting audit. But just recording the lighting level (known as the lux level) in the various rooms is not enough. We need to assess the effectiveness of the installation.

During a recent energy audit several lighting fittings (as shown in the photograph) were discovered. Perhaps discovered is the wrong word, the high intensity fittings were plainly obvious.

Pairs of uplighting fittings were installed close to each other, and very close to the ceiling.

These fittings didn’t add any value to the illumination of the space, as you can clearly see these intended uplighters only created an intense, localised pool of light (and heat).

Based on operating 3,600 hours per year, each fitting wastes HK$ 660 per year in electricity. Just measuring the lighting level is not sufficient for an energy audit, in this case immediate removal was recommended saving electricity.

Also remember that in air conditioned rooms removing lighting fittings not only lowers the electricity consumption for lighting, it also lowers the heat gain which in turn reduces the load on the air conditioning system. As a rule of thumb, eliminting 1 Kw of lighting lowers the total electricity consumption by 1.3 kw.

Don’t forget to check your utility tariff

DON’T forget the electricity tariff – It is easy to overlook the painless cost savings achievable by simply choosing the correct Utility Tariff for your facility or building.  A tariff is the published rate for electricity charging, typically utilities offer different charging schemas for low, medium and high consumers.

Tariff Analysis is a scientific based approach, examining your the utility bills to identify the optimum tariff for you, that the tariff with the lowest cost.

Where the utility company permits summation metering, and the facility has more than one power meter, re-analyse using the totalled data – using all the meter readings, to check and identify if summation metering provides a beneficial tariff.

Remember that tariffs change frequently and without notice,  so its wise to ensure that you order a Tariff Analysis at least once per year.