The quote that makes up the recognized title of this essay comes from Ronald Reagan. Here is the entire quote –
I think I could sum up my position on this with the recitation of a brief Russian proverb “Doveryai no Proveryai.” It means trust but verify. -President Ronald Reagan in the “New York Times”, Dec. 4, 1987
Well i have been chronicaling the bring up of my “green” home in Tiburon. But perhaps it has not been said clearly enough that the entire project would have failed pretty much if I had not taken the step to take data and then verify the data against what were the system specifications of the claims for each of the products. So before the home settles down to long term stable operation let me tell you about a few of these and then make some comments.
- Solar photovoltaic panels were installed on our roof in 2 separate installations because the home has a separate address for a rental unit. This qualified us for 2 separate rebates. The larger set ended up having a intermittently faulty inverter that had to be replaced. Without monitoring with a resolution of 5 minutes per data point we would not have been able to spot the problem that ended up causing us to lose perhaps 25% of our total output.
- The solar panels that were installed second (for the rental apartment) have an unexpected shading that occurs in the afternoon only in the time period from Novermber 1 to February 1. This also removes about 25% of the output of these panels and can be improved by a simple tree trimming.
- Our solar hot water system has a faulty controller that does not restart upon a power failure and hos other features that if used in “normal” ways will crash due to software bugs. i am working with the vendor to have this fixed still.
- We decided to take out the older natural gas fired furnaces and to put in heat pumps (but with natural gas backup) into the home because we anticipated being able to generate sufficient electricity to be able to use our solar energy excess in the summer to power the home heating in the winter. This looks like it is going to work out fine but our heat pumps appear to be performing way below expectations. So we are having them tested to see if they are performing to their specifications. This is a most difficult task to get done as no contractor likes to be seen as doing incomplete or work in error and there are no independent verifications services I have found. Ouch. Something in the home where its performance cannot be verified is a open door to sub optimal performance.
- Our hot water system in the home was designed with a recirculating loop so that when we turned on a faucet or shower it would deliver hot water to the user in a few seconds. It worked very well but the original design had the recirculating pump on 24 hours a day. Even if you turn it off at night and perhaps when you are at work it will double or triple your overall hot water energy use (gas in this case). So we had to design an alternative. What we eventually settled upon was a switch in every bathroom where a person, with a simple touch, can turn on the recirculating pump for a total of 3 minutes after which it automatically turns off. Ergonomically this is a bit of a nuisance because you need to wait typically 1-2 minutes before the hot water arrives at your location. But generally this wastes little water and little natural gas. So it is optimal except for the human waiting which can be often planned (when you wish to shower touch the hot water prep button and then go and undress, get new clothes, etc and when you are ready for the shower it is prepared for you as well!)
- The hot water system works (as was described earlier) by the sun working to raise the water temperature of a storage tank as much as possible during the day. And then the water is pulled from this tank as various users call for it. This hot water tank has the water temperature further raised if needed by a pair of tankless water heaters that are fired by natural gas. One additional problem we identified was that the storage tank has heat leaks so that if the sun raises the tank to 100F one day but we shower the next morning the tank has often dropped down by almost 20F to around 80F when we call for the water. if we can find and plug these heat leaks through better insulation and more careful handling of the water then this can improve substantially.
In each of the above cases, I envision a future where our President Obama and the new congress, who are eager to begin to address climate change, encourage us all to make changes similar to what I have done in Tiburon.
With out verifying what we have install to be working properly and working well over the long term we will not really reap the fruits of what we will labor for and spend precious capital.
Trust but Verify. I am sure the old sage would say the same thing in this new context today.