Rick [Fedrizzi, President & CEO, USGBC], thanks for the nice comments and we do miss you at Carrier and UTC. Mayor Daley and other distinguished guests, welcome. Welcome also to those joining us via the Web.
Rick has introduced GreenBuild365 and UTC is delighted to make this possible. We’ve heard one of Rick’s and USGBC’s goals is to promote the building of green schools through wider awareness. I’ll go further and say GreenBuild365’s purpose overall is to promote the seriousness of the global warming challenge and the advantages and benefits of green for all kinds of buildings and to all kinds of audiences both domestic and worldwide.
A primary reason to support GreenBuild365 comes from a remarkable survey conducted in the last year by the WBSCD’s Energy Efficiency in Buildings project. This concludes that respondents on average (and the survey group includes sophisticated groups like developers, architects, mechanical consultants, and contractors) overestimate the cost of building green and underestimate the impacts. Specifically, respondents think the cost increase is 17% where we believe the actual increase is 5%. And they think CO2 emissions from buildings are as low as 19% of world total where the number on study is twice this at 40%. These are big differences and clearly enough to swing countless buildings design choices. So awareness counts.
I have a message of great optimism today. We’re all hearing carbon footprint goals from mayors of the largest cities around the world. Mayor Bloomberg has committed to 30% less by 2030. Mayor Livingstone of London to 20% by 2020. Since we provide many of the technologies and products that will make these goals happen, my message is the optimistic but realistic one that it’s all possible and actually not that hard.
Just for background, United Technologies Corporation has about $54 billion in revenues and builds aircraft jet engines (Pratt & Whitney), helicopters (Sikorsky), elevators (Otis), heating and air conditioning systems (Carrier), fire protection and security systems, aircraft and space systems, and even the space suits for the American space program. Last, we build hydrogen powered fuel cells and a line of on-site co-gen products of particular interest today.
Why these products are important is that the common denominator of every single thing we do is to convert energy to useful work, whether elevators or air conditioning or aerospace. The dark side is that our equipment over a huge installed base over decades accounts for 2% of greenhouse gas emissions worldwide every single day. The bright side is we know lots about the physics and technologies involved, we know what can be achieved, and the gains are huge.
Let’s start with the fact that 91 percent of total energy coming out of the ground is lost or wasted before it becomes useful work. It doesn’t have to be that way, not remotely. A glaring example is that half of the input energy in central station power plants goes up the stack as waste heat because we can't move heat effectively any distance at all. But how about putting the generation on-site and capturing and using the waste heat there. We do this routinely, and the answer is that energy conversion efficiencies (kilowatts or work out relative to Btus in) go from percentages in the 30s for central station plants to more than 75 percent for generation and heat capture locally.
A second glaring example is not recapturing input energy into vehicles and other accelerated objects when they're braked. Isaac Newton taught us that the net energy in this acceleration/deceleration cycle is zero, adjusted only for system inefficiencies and losses. A good way to think about this is elevators. New ones recapture the energy on descent that was expended on ascent. The result is that Otis elevators today that use 75 percent less electric energy than the same equipment in speed and load did a decade ago. Said another way, a re-generative commercial building high rise elevator lifts a million pounds a day for a net energy cost of a dollar an hour.
A third big example is heat transfer instead of generation. Realize first that air conditioning systems do not cool air in a direct sense like food in a refrigerator. Instead they move heat from one place (inside) to another place (outside). We measure the efficiency of air conditioning systems by Coefficient of Performance (COP). It's the amount of energy required to move another amount of energy (in this case the caloric content of the heat moved). Air conditioning systems worldwide work this way, and the COP is about 4 times. In other words, one unit of input is needed to move four units of energy or heat.
So how about heating hot water by heat transfer. We're learning a startling statistic from the WBCSD buildings inventory worldwide. The numbers vary but about 15 percent of total building energy consumption, whether residential or commercial, heats hot water. The old way is direct insertion of heat into the water, just as we did thousands of years ago over the campfire. But it’s also entirely feasible to heat hot water via heat transfer with COPs like air conditioning, or about 4 times. So energy can go down by 75 percent, which means more than a 10% reduction in energy consumption in total for buildings which themselves account for 40% of all energy consumption worldwide. Paybacks for systems like this are about three years at current energy prices.
The point of all three examples is that energy conservation in significant amounts is feasible today and reflects the laws of physics. And not only feasible but with attractive financial returns.
Let’s say Chicago has 3 million inhabitants, 400,000 residential and commercial buildings, and about 1.5 million cars. Together these consume 70 terawatt hours of total energy annually. Which is the last time you'll hear me use that term today since none of us can keep track of the zeros. I'll instead convert terawatt hours into power plant equivalents for Chicago energy sources of all kinds. Let’s use a typical large power plant of 700 MW which means the City would need in total about 11 such plants. However measured, it's a lot and significantly more per capita than in many cities worldwide.
A surprising 80 percent of this total Chicago energy load is for buildings, or about 9 power plants. Transportation accounts for virtually all the rest. By function we estimate that the buildings energy load breaks down as heating (38 percentage points), lighting (6 percentage points), hot water (11 percentage points), appliances and equipment (22 percentage points), and air conditioning (3 percentage points).
So where do we start. First is setbacks on heating/cooling/lighting for residential and office space when not occupied in off hours during the day for residences and at night for commercial space. Both would save about 5 percent of their current total energy load, or about 1/3 of a power plant for Chicago in total.
Another is the hot water heating example earlier. About 1¼ power plants. Another is re-generative elevators although their total energy load isn't enough to make the power plant savings meaningful. But we could extend the same reasoning to cars which would save at least another half a power plant. Bear in mind that hybrids do this already by capturing braking energy while re-charging the battery.
Fourth is on-site power generation enabling heat recapture and re-use rather than central station plants. We build products like this today, with the recaptured heat driving heating, hot water, air conditioning, and even refrigeration. Potentially another 1¼ power plants.
Together a little less than 3½ plants out of Chicago’s 11 total, or say 30 percent. This won’t come cheaply with retrofits versus new construction but it’s what a greenfield city would look like, and lots of the gains can be had with attractive returns even on a retrofit basis.
I skipped the transportation opportunity today to save time for buildings but mention in closing fuel cell powered buses. We build them, deriving from our experience since the 1960s in building all the fuel cell power plants for the American space program. Why do we have hydrogen powered fuel cells in space. Because the by-products (and there are only three) are water, heat, and electricity. Astronauts drink the water and the other two by-products heat and power the Shuttle. The same is true for a fuel cell powered bus although the water here ends up vented harmlessly to the atmosphere.
There are about 3100 diesel buses here in Chicago. Although fuel cell buses are about twice as efficient, there’s still not a lot of energy involved relative to Chicago’s total so the savings aren’t that great. But diesel buses emit oxides of sulfur and nitrogen and lots of these, plus generate the noise so familiar and unpleasant to all of us. By contrast, fuel cell buses have no emissions, none. No smell, none. No noise beyond conversational speech. By the way, there’s a UTC fuel cell buses outside. It’s available for tours and/or rides and I urge you to take a look. One thing you may note is that the air conditioning is the largest noise source by a margin and because this is what you notice now we’re going to get rid of it also.
The reminder in closing is that this is about fundamental physics and nothing more: capturing and re-using otherwise waste heat, capturing the energy of acceleration when decelerating, and heating via heat transfer rather than directly over a heat source. The fact that 91 percent of total energy is wasted every single day rather than becoming useful work sizes the opportunity for us, and it’s evidently huge.
