CRES 2007 Renewable Energy and Sustainable Design in Buildings Award (HOME)
Winner: Multi-Family Buildings Category

Energy and Conservation Information (predicted):

Annual solar electricity production: 34,382 kWh/year Annual electricity bill savings @ $0.09/kWh: $3.094/year Annual CO2 emissions reduced: 70,414 Ibs/year Equivalent reduction in vehicle miles driven: 77,020 miles/year Equivalent number of trees planted (total): 2,708 trees Cups of coffee brewed with solar electricity: 1,127,540 cups/year Fruit smoothies blended with solar electricity: 12.337,920 smoothies/year

Residences at Creekside
1700 Pierce Street
Lakewood, CO 80214

Participants:
Bill Lunsford - Housing Development Manager
Richard Kuhn - Construction Manager,
Sue Reilly - Enermodal Engineering, Inc.
Namaste Solar Electric
Energy Outreach Colorado

This building is an excellent example of integrating sustainable features into an affordable-housing building. This property can provide an excellent example for both market-rate and affordable housing developers to make their developments more energy-efficient and also keep the cost under control.

The 119-unit apartment building has a square footage of 130,000, including the parking garage. Construction costs were $98 per square foot. It was completed in April, 2007 and occupied in May, 2007.

Use of Renewable Energy

• 25,000 Watt Photovoltaic array (144 panels)
• The building is 6 stories tall with the long axis east-west, offering an excellent, unobstructed southern exposure
• Fourteen WaterCycle units which re-cycle heat from waste water to pre-heat hot water.
• Low-E double pane windows
• All fluorescent lighting
• EnergyStar appliances wherever possible (we have found no E Star rated ranges)
• Passive solar component: overhanging balconies on the south side of the building shade the patio doors below from much of the summer sun, but allow the winter sun into the apartments. Balconies above the sixth floor serve this function exclusively.
• R 19 insulation in about 50% of the exterior walls. R 15 in the remainder.
• The site's monument sign lighting is powered by a solar electric system.

The 144 Kyocera photovoltaic panels are mounted on the roof and not visible from below, eliminating concerns about reflection and glare.

Environmental Impact

The energy efficiency strategies include high performance windows, high efficiency lighting in the common areas and living units, condensing boilers, gray water heat recovery and a 25 kW photovoltaic system

The windows have low-conductivity vinyl :frames and solar-control low-E glazing. The windows will save about $1500 per year and pay for themselves in less than 14 years. Just as important, the windows will also provide a much more comfortable living environment.

In this 120-unit apartment building, lighting is the largest end use and Lakewood Housing and the design team arrived at a high quality design through the use of fluorescent fixtures. The original design relied on incandescents in the living units, which is standard in multi-family housing. The final design is more expensive, but the payback from energy savings is between 5 and 14 years not including EOC grant money and Xcel rebates.

Hot water to the units is provided by 92% efficient, condensing boilers. These have less than an 8 year payback given today's natural gas prices.

In addition to the boilers, gray water heat recovery was incorporated into the design. The WaterCycle heat exchangers are simple passive devices that recover heat from the drain water to preheat the incoming supply water to the boilers. Because the living units are stacked, the project only required 14 WaterCycle units to serve the building. The expected payback is less than 5 years, again excluding the offset from grants through OEMC and EOC.

The total savings from these energy efficiency measures is estimated at 76,600 kWh/yr and 6,000 therms/yr. This is a reduction of 210,000 lbs/yr of CO2.

Aesthetics

The solar array on the roof is situated so that it is not visible from below, eliminating concerns about reflection and glare. All WaterCycle units are within wall cavities and therefore not obtrusive. Balconies serve their traditional purpose as well as providing shade for the units below.

Public Awareness

Although not a public building, Creekside gives pre-arranged tours regularly. The solar system specifically has a graphic-video display ("Fat Spaniel"), which illustrates the electricity being generated on a real-time basis as well historic production. This display is located in a kiosk in the main Community Room for all to see.

There is a framed display about the Water Cycle devices located in a first floor corridor, directly in front of one of the enclosed systems. It describes how the systems work and the energy they save.