Co-Gen Unit Installed--Finally!

After 14 months, finally, the Ecopower combined heat and power unit (CHP) is installed. It has been running now for about 3 weeks, and after some initial debugging, it seems to be working well. Above is a picture of the unit in our basement. The Ecopower is clearly in the foreground. The silvery thing behind and to the right is a new water storage tank that is in addition to my normal hot water tank (to the left and behind the copper pipes), and this new tank acts as a heat storage unit.

According to the installer, this unit is indeed the first residential co-gen unit installed in Connecticut.

The unit is very quiet. We never hear it upstairs while it is running. This surely beats having a noisey back-up generator in the back yard. Our CHP is presently grid-tied which means that it is not set up for backup power. In the case of a power failure, the CHP will also go down. This will change once the "island mode" electronics become available. Current target date for that is December, 2008, but given the amount of time it took for this thing to become installed, I'm not so optimistic that it will be ready then. We'll see.

I've been monitoring the power this generates (5 KW max power) on a daily basis and will post some graphs in due time. It seems to be generating about 40% of our monthly baseload power while satisfying our hot water usage (I can't say "hot water needs" because we definitely use more than we need!). The heating season is over, so we won't know about the winter power generation until it gets cold enough again in the late fall.

This past winter provided some opportunities to determine our (past) heating oil use vs. our geothermal heat pump power use, and I want to post that data first for comparison to our new system.

Funny thing about this co-gen unit. We agreed to purchase it in February, 2007. Since then, the oil situation has changed for the worse. While I'm still glad we got this thing, it seems our next goal will be to make the ecopower less critical to the daily house operation. This CHP technology is a great improvement efficiency-wise, but I can't help but wonder if it isn't coming 20 years too late.

Discoloration of Solar Panels

One problem I've seen with our Sunpower solar panels was that about half of them have air-pockets in them. You can see this in the above picture as the light green areas on the panels.

I've let this problem fester for some time, but while at the Earthday celebration (where our efforts were acknowledged), the company who installed the panels had a booth, and I told them about the problem. They said that this was a known defect, and that Sunpower will replace the panels.

After a few days letting the wheels turn on this, Sunpower has decided to replace all of my panels, because replacing only half of them would not work out well. Apparently, my panels are now obsolete (after 2 years!). So far, they have worked as advertised, despite the defects.

Bottom line: We get a new solar panel array sometime near Labor Day this year. Will update on that when appropriate. Until then, there is plenty to write about.

Work Honored By Local Group

So someone is noticing anyway.

We were honored by the Westport Green Energy Task Force for our "green" residential efforts. The awards ceremony was on the Saturday after Earthday at the local nature center (Earthplace). Westport's First Selectman (essentially the Mayor of Westport) gave out the awards. Some of the local press showed up too and had small blurbs about the event.

A fun time was had by all. The kids loved the sea-life exhibit for the Earthday celebration. They had live shellfish from the Long Island Sound for the kids to touch and look at.

The Best Oil Interview I've Seen in a Long Time

Usually, I have my TV set to the CNBC business channel during the day while working, but 99% of the time, the sound is muted. The best expression I've heard for this station is "bubblevision," and it is a good description of the cheerleading that goes on during most programs.

There are a few people for which I have an exception to the mute rule, and one of those is Texas oil and gas man T. Boone Pickens. You can see find some of the interview in the video at www.cnbc.com. As I was typing up this note, I decided to review the video, and what is interesting is that they cut the first half off, and it was the better half! The second half is still good and worth viewing. He mentioned that with the present oil price, the USA is now sending over half a trillion dollars a year overseas to purchase oil, and that we are pretty much heading for a disaster in this country if we don't change our energy policy, and further, that none of the presidential candidates seem to be clued into the problem.

Boone Pickens is a man who understands the issues that set me off on my treck to "go green." With time more and more seem to be coming around to this view. The question in my mind is will we reach critical mass soon enough to prevent a pending disaster?

Local Green Energy Task Force Cited in NY Times

On Thursday, 17-Jan-2008, there was a local showing of the environmental movie "Everything's Cool." The event was picked up by the New York Times (click on the link to go to the article). I attended this event with my son, but we had to leave early, for it was a school night, and we missed the bulk of the discussion afterward. Information on the film is found at its website.

It was a good movie about the global warming movement. What was missing, I think, is what is missing a lot in these discussions, namely a discussion about our energy security.

The green energy movement is indeed growing in Westport. The Green Energy Task Force has recently published a report on the local greenhouse gas emissions, and it can be found here. Already, the town has installed solar panels on the Firehouse roof. There is a lot of work to do still, but, as the euphemism says, the train has left the station.

Micro Combined Heat and Power

About a year ago, I read an article about small-scale or micro combined heat and power (CHP) units. In the traditional situation, you burn fuel locally for water and space heating, and you get electricity from the grid. That electricity comes from a power plant that is producing an enormous amount of excess heat. Wouldn't it be good to be able to capture that heat for use in water and space heating? Alternatively, how about putting the power plant locally, so you can use the excess heat? That is what the micro-CHP is all about: local power generation combined with heat capture.

Immediately, I contacted the company that was offering CHP generators for commercial and residential applications. I signed a contract for a unit last February, and I've been waiting ever since for the installation. Part of the problem was that the engine was not UL rated, and apparently they spent some time getting the unit through all the tests. We are currently waiting for Connecticut Light and Power to grant approval to connect this to the power grid. There shouldn't be any problem, for the solar panels have already been approved for grid-tie. In pushing the envelope in this area, I've noticed you have to spend a lot of time waiting for things to get done.

In my mind, this co-generation technology will be revolutionizing power generation. We are about to the break the utility monopoly paradigm, and it will be economical, because, as shown in the last post, an enormous amount of energy is wasted in the traditional power generation scheme. With local production, you can gain back the lost heat for local uses, and the savings will offset the so-called economies of scale that larger power plants offer. It isn't clear if this is available everywhere, but in the State of Connecticut, they are committed to introducing cleaner power technologies, and CHP certainly qualifies.

Distributed or local generation offers other advantages as well. First among them is that the need for power lines is reduced, and so are the losses associated with them. Distributed generation also allows for (but does not guarantee) a more stable grid structure. This is a big deal locally, where the power company is running new underground high voltage lines in an effort to increase the grid robustness (and more than likely, to increase the amount of power they can sell into Long Island). If the distributed generation takes off, we will not be needing to do much more of that--ever.

Information on combined heat and power units is given at the Marathon Engine website. Here is a diagram of a typical layout. (Click on the figure for a larger image.)



I will be posting more information on our actual configuration at a later date. This technology presently is not economical for the average residence (although with some changes, I think it could be), but because we have geothermal heat pumps, we use about twice as much power (with a corresponding reducton in fuel use for heating) as the average residence, and this helps make our installation economical. I'm hoping on synergies between the the CHP and the geothermal that will then make the geothermal even more economical, but for now, I'm just waiting for this to get installed to actually measure how much we will be saving with the CHP.

Lots of Wasted Energy

If you spend any time looking at the national energy complex, one eye-catching part is the amount of energy that is lost to waste heat in the electric and transportation systems. In the following flowchart from the Lawrence Livermore National Laboratory, the energy flow in the USA energy system in 2002 is shown.




EIA has similar flowcharts similar to this on their website for all parts of the energy system. To see this flowchart effectively, you may have to open it up in a new window by right-clicking on it. While a little out of date, the numbers are still fairly close to what is used today in 2007 (we use over 100 Quads now), and the ratios are very close. In case you have forgotten, one Quad represents one quadrillion BTUs or British Thermal Units--a unit of energy that is so arcane that even the British no longer use it, but we Americans seem bound to it forever. For completeness, a BTU is the amount of heat required to raise the temperature of one pound of water from 60 degrees Fahrenheit to 61 degrees. Arcane, indeed, but we need not go there.

The numbers are staggering. In the electric system, close to 70% of the energy is lost to waste heat. In the transportation system, which dominated by petroleum, the loss is closer to 80%. The size of the numbers makes sense if you think about it. Most of the energy used by your car goes away in heat from the engine, and only about 20% is converted into making the car and its contents move. (Critics like Amory Lovins go even further and point out that most of that useful power is used to move the car and not the people in the car, and so the amount lost is 90-99%.) In the electric system, about 60-63% is lost to waste heat, and the bulk of the remainder (7-10%) is lost in transmission.

There are ways to capture most of this wasted energy. It is hard to use it to make more power, for you are fighting the 2nd Law of Thermodynamics (entropy). However, if what you want is the heat instead of the power, then you are in business.

If you look at how we use fossil fuels, a large fraction goes to heat: space heat, water heat, dryer heat, oven heat, etc. The way we traditionally do it, however, doesn't make a lot of sense (or, at least not any more). We burn coal at the power plant to make electricity, and the excess heat goes up the stack or into the cooling pond. We then take that power off the grid and start up the oven or the dryer. Further, we burn heating oil or natural gas in the furnace or boiler to heat the water or the house.

What if we were to take to power plant and put it in the basement? That is the idea of combined heat and power or cogen units. Instead of one big electric plant powering hundreds of sites, we distribute the generation out to the places where it is used. The excess heat is also used locally in other processes instead of being dispersed into the atmosphere, streams, lakes and oceans. We are about to do just that in our house. More details to follow as the cogen unit gets installed.