My TED

I've been using a TED whole house energy monitor for about 9 months which shows us energy use, solar feed, and net energy to about a 3 second resolution. It also feeds Google Power Meter which is simple but has some useful graphing over time. Its great and has really helped me refine our energy use. I was finally able to confirm the geo runtime kw and also how often it runs in various states. Given that the geo makes up 50-67% of our energy use, fine tuning that has a huge impact.

I had noticed that TED was about 10-15% higher than my solar vs. what my Internet connected inverter box told me. All of these monitors are only estimates as they take second by second readings and estimate over time. Precision differences even between 1 and 3 second resolution can be notable. The other odd thing was that when I was generating a lot of energy but using little, TED would report not only negative net but also that my usage alone was negative which obviously isn't possible. It was a small amount so just chalked it up to rounding errors.

I was excited to receive my first utility bill to see how we did. I was disappointed to see that TED was 15%+ optimistic on our net energy usage and energy generation. It varied bill to bill (we have great variations in energy usage/generation between winter and summer due to solar and geo) but generally was in that range. I read on the TED forums of others reporting similar esp. with solar connected systems. TED responded saying they would put a calibration function in their software so we could individually tweak it toward reality.

I finally got the software update and applied it a couple of weeks ago. However, it had the counter effect as I calibrated down on solar but up on feed. When the feed inexplicably went negative during heavy generation it now went 15% more negative (in the wrong direction). I posted about it on the TED forums and got a response from a TED admin saying I probably had badly calibrated MTUs. I called the office and I have new ones coming which hopefully solve the issue. I have 15% bad data over the 9 months but at least that was relatively consistent so I can correct. Tune in post Labor Day when I install the new ones.