We specialize in maintenance, so we gravitate toward lighting fixtures that are well-designed and
provide the longest proven maintenance-free service. We have extensive experience in assisting in the
selection of appropriate fixtures, performing test installations, light level studies, and helping our
customers promote the financial and environmental benefits of the initiative. Our objective is to
provide both vendor neutral and objective information to the City, enabling informed decisions at each
project phase.
Energy Savings Analysis
The baseline for the project will be calculated using the current energy consumption based upon the
existing Eversource inventory and utility bills, adjusted as necessary based on the field audit. The
change in energy consumption as a result of the streetlight conversion is the difference between the
baseline and the “light-by-light” recommended LED replacement fixture. The energy savings will be
calculated using the approved LM79 test results for the proposed fixtures to identify the new wattages
and energy consumption of each proposed unit.
The baseline calculation for unmetered streetlights is simple and straightforward: fixture watts x
number of fixtures at that wattage x assumed Eversource operating hours = fixture class kilowatt hours.
This calculation is repeated for all fixture classes (wattages) and summed to equal the total energy use.
The same method is used to compute energy use associated with new LED fixtures and the energy
savings is the difference between the two. Energy savings in Year 1 is based on the customer’s existing
distribution and supply rates as confirmed by recent electric bills. Energy savings over a longer period
generally assumes an annual escalation rate.
Operational savings is a customer-driven estimate as only the customer has the most accurate
information regarding existing labor and materials costs if the streetlights were municipal-owned prior
to the conversion. Also, the customer must determine if labor + benefit/pension costs should be
assumed due to staff reduction or assumed as zero if current staff levels are to be maintained.
Based on our preliminary energy analysis from the vendor quotes received to date, Siemens
anticipates that the City’s energy saving, as measured in kilowatt-hours, will range from 60-65%. This
represents an approximate 60-65% reduction in operating costs on both potions of the City’s monthly
charge: 1) charges are kWh-based and 2) reduction in fixed charges.
Procurement
For the purposes of this response to quantify the cost/benefit of various manufacturer options,
Siemens explored the following options:
LED streetlight fixture pricing was sourced from the following 3 manufacturers:
* Leotek
* Philips
* Acuity
Wireless controls pricing was sourced from the following 3 manufacturers:
* Cimcon
* Philips CityTouch
* Acuity/ROAM
9225 Bee Cave Rd www.siemens.usa.com
Building B, Ste 101 §12-837-8000
Austin, TX 78733 Page 18
