The Boston Synagogue

A view from the front of Boston Synagogue with the new Heat Pump

On April 10, 2010, Boston Synagogue was presented with a "Leading By Example" award by Massachusetts Interfaith Power and Light in honor of the Synagogue's greentech efforts. The award was presented at MIPL's annual meeting and celebration of the 40th Anniversary of Earth Day.

At Boston Synagogue, we take seriously our responsibility to further the Jewish concept of 'tikkun olam,' or repairing/perfecting the world.

A few years ago, we began to study what we could do to reduce our carbon footprint and energy consumption.

As a starting point, we joined the Massachusetts Interfaith Power and Light consortium (MIPL) -- a group of churches and synagogues that shares best practices on energy conservation. They did an initial evaluation of our situation.

Our basic problem was that we had a beautiful early '70s building with minimal insulation and with a highly energy-inefficient heating and cooling plant. The initial prospects for making a substantive difference were not promising.

However, we refused to give up, and be our original membrane roofing anyway, we decided to pay extra to install several inches of additional insulation underneath. More recently, we replaced incandescent floodlights in our hallway that were 'on' 24/7 with fluorescent lighting. The annual savings from the light bulbs was surprising large. We also weatherproofegan by making small changes. One initial focus was improved insulation. Since we needed to replaced our doors.

Our biggest move was a complete (and expensive) revamping of our HVAC plant in stages over a two year period. In the summer of 2008, we were forced to make some fundamental HVAC decisions, when our almost-forty year old system completely died. The existing (original) heating system relied on generating steam in a coal buring power station somewhere in Boston, piping the steam across the city, using the steam to heat air in the synagogue basement, and forcing the heated air through ducts in the building until the sanctuary started to warm up. In addition to being highly inefficient and expensive, this system required several hours to heat the space once it was turned on.

An energy system analysis showed that what we really wanted to do was simply to transfer heat from the outside air to the interior space as efficiently as possible (and vice versa during the air conditioning season in summer). After reviewing the alternatives, we decided on an air-source heat pump system with a variable compressor that only worked as hard as needed, and which generated hot/cold air in the sanctuary space within minutes of turn-on. One characteristic of these heat pumps is that they can transfer four to five times as much heat between the exterior and interior of the building, as compared with the equiivalent electrical energy input.

Two years later (2010), we were seeing dollar energy savings of 57% and BTU savings of 70%. We also benefited from a substantial reduction in repair bills. As a result, we estimated that the payback period would be approximately 5 years (not including donations to defray some of the capital costs).

The details of our decisionmaking process can be seen in the MIPL Boston Synagogue Case Study.

And we're still not finished! In 2010-2011, we replaced our 40 year old commercial refrigerator and backup residential-grade refrigerator with Energy Star units.

And in time for the 2011 High Holidays, we have installed high-efficiency Light-Emitting Diode lights (LEDs) in many of our existing light fixtures, including the floodlights high in the ceiling over the Holy Ark.

Unlike old style incandescent filament bulbs, which convert only 10 per cent of the electrical energy input into light (the rest is waste heat), LEDs convert half or more of the energy input into visible light.

The 18 watt LEDs replace 75 to 100 watt incandescents and provide better quality lighting, thus reducing our carbon footprint and electricity bills even further.

In addition to their high energy efficiency, LEDs last for an extremely long time. The units we have installed are rated for 25,000 hours operation (although no one really knows, since LEDs have not been around long enough to be tested to failure!). Since the lights in the Synagogue are on for an average of 10 hours per week, this means that these lights should last for at least 2,500 weeks or fifty years – the closest thing that we have to an “Eternal Light”!