Wednesday, April 22, 2009

Dual Screens Increase Productivity

Does having a second monitor make people more productive? Is this productivity enough to offset the additional environmental impacts? What about the additional costs? Our quick study results indicate yes people are more productive, this productivity most likely offsets any added environmental impacts, and it definitely offsets the additional costs.


About six months ago we purchased a second 19”

monitor for our Green Building Services team to help save paper, reduce energy consumption, and increase productivity. The idea came from a very forward thinking project manager, George Oommen, who wanted to get the project team designing and building a new laboratory building to “go paperless.” With the help of Tim Scruby from Facility Dynamics Engineering (who never prints drawings) to demonstrate how to view entire drawings with one screen while zooming in on details in the other, George urged the team to go entirely paperless and even offered to buy team members a second monitor. He calculated the cost of the second monitor would be much less expensive than the cost of printing drawings and having them couriered back and forth.


Following up on George’s excellent idea, I did some research on the potential environmental impacts. There is lots of anecdotal evidence that points to employees being more productive with larger screens (or multiple screens), and some attempt to quantify this including a study done by the University of Utah, which showed two monitors to be 29% more effective for tasks, 24% more comfortable to use in tasks, and 39% easier to move around sources of information (found here). There wasn’t any information about environmental benefit, but it stands to reason that if people are that much more productive, they’ll be at their computers less and use less energy as a result.


In April, 2009 we conducted a survey of the 6 employees (including Jessica Parks, pictured above) using the second monitor to see if they felt they were more productive and / or reducing environmental impact. A summary of the results can be seen above and the full results can be found here. All employees felt the second monitor increased productivity, with responses ranging from a 5 to 10% increase to a greater than 50% increase. Surprisingly, only 50% of the team felt the increased productivity offset the additional environmental impacts from powering the second monitor, while 83% felt the increased productivity offset the additional costs (first costs and operational costs) of having the second monitor. 100% of the respondents said they “always use” the second monitor and that it increased their productivity when working on Word documents or Excel spreadsheets.


Following up on whether or not the increased energy consumption and costs were offset by the productivity increase, I’ve conducted a conservative analysis of environmental and financial impacts from a 20% and 5% increase in productivity. If people work 250 days per year, 8 hours per day, their second monitor will cost us $6.60 in electricity per year ($0.15 / kWh) and emit 0.0165 Metric Tons of Carbon Dioxide Equivalent (MTCDE). If they would have to work an additional 20% (50 hours) per year (if not for the extra monitor) to complete the same tasks, they would use an additional $11.40 in electricity and emit 0.0285 MTCDE (1 CPU, 1 monitor, 1 light fixture). In this case, the GHG emissions reductions from having a second monitor offset the emissions added from the extra plug load. If people are only 5% more productive, we don’t save MTCDE (0.0165 from 2nd monitor vs. 0.007125 from running CPU, 1 monitor & 1 fixture 5% longer). This analysis changes if you have more than one light fixture on of course (all of our fixtures are controlled by fixture-integrated occupancy sensors and are likely to turn off after 10 minutes of inactivity so I’ve only counted the fixture directly overhead). Electricity demand was estimated for the light fixtures (50 watts per fixture with two 4’ T5 lamps) and measured with a Watts Up? Meter from Electronic Educational Devices, Inc. for the second monitor (22 watts) and the CPU and first monitor (140 watts). Greenhouse gas emissions were taken from the recent ISO New England emissions factor of 0.000375 MTCDE / kWh. I have not included the environmental benefit of reduced printing because of the second screen.


On average, our employees cost us about $90,000 per year with salary, fringe, and overhead. If we get an extra 20% of productivity out of one of them, we’re getting $18,000 in “free” labor. This drops to $4,500 if they’re 5% more productive, but in either case the labor savings more than offsets the few hundred dollar capital expense and the $6.60 annual operating cost. Again, I have not included the financial impact of reduced printing. The savings would also go up if applied to higher salaried employees.


Based on the responses to the survey and the results of financial and environmental analysis, it seems adding a second monitor is extremely beneficial. We had to convince our IT department that we had a need for them (they were very clear that they wouldn’t accept the increased productivity argument regardless of the evidence supporting this), but the necessity to view project drawings was sufficient to make this happen. In most organizations, the increased employee productivity should be enough to justify the decision.

Thursday, April 9, 2009

Dual Flush in Egypt

This dual flush toilet photo was taken in Egypt and sent in by Fulbright Scholar Alicia Harley (formerly of the Harvard Office for Sustainability). We don't know / can't read the make, model or flow, but it looks like a tank-type toilet (gravity fed) with the tank in the wall between the wall studs. We assume the larger button gives a half flush (probably a 6 liter "solid" flush and a 3 liter "liquid" flush). Alicia is in Egypt working on the issue of access to safe drinking water, so it is good to see they're reducing the amount of potable water used in their toilets. Thanks Alicia

Wednesday, April 8, 2009

Low Flow Showers


The Malcolm Athletic Center (MAC) at Harvard University has replaced all of its shower heads with low-flow versions. They use the Delta H20 Kinetic showers, which are rated at 1.6 gallons of water per minute at 80 psi pressure, down 36% from the 2.5 gpm standard in the United States. As a user of the facilities, I can say that the old showers aren't missed.

Friday, April 3, 2009

Fume Hood Ventilation


The Jacobsen Lab in Harvard University's Mallinckrodt Building uses Mott variable volume fume hoods to help save energy by reducing the volume of air being exhausted (and as a result reducing the fresh air brought into the space that needs to be heated or cooled) as the hood sash is closed. The hoods are saving additional energy by having air movement with 80 feet per minute face velocity entering the hood, reduced from the typical 100 fpm or higher in most hoods (the hood was tested and demonstrated safe containment at 60 fpm). To ensure occupant safety, each hood has a digital display indicating the face velocity, with an alarm sounding if it were to go too low and a purge button that allows the occupant to increase volume to 300% of normal if there is a spill. Occupants are educated about the hoods' operations and then provided with large digital displays at the entrance to the lab that indicate total volume of air being exhausted in cubic feet per minute. Lab users know what the volume should be if all hoods are closed and can quickly assess whether a hood was left open and is unnecessarily wasting energy (as Philip Kreycik is doing in the pictures above and below). The newly renovated Jacobsen lab is pursuing a Gold rating from the US Green Building Council's Commercial Interior rating system and has integrated a number of sustainable design elements into the project.