The Data Kraken wants to grow new tentacles. I am playing with the CMI – Control and Monitoring Interface – the logger / ‘ethernet gateway’ connected to our control units (UVR1611, UVR16x2) via CAN bus. The CMI has become a little Data Kraken itself: Inputs and outputs can be created for CAN bus and Modbus, […]Read More Logging Fun with UVR16x2: Photovoltaic Generator – Modbus – CAN Bus
This is one of the perennial top search terms for this blog. Anticlimactic answer: Yes, because input and output are determined also by economics, not only by physics. Often readers search for the efficiency of a refrigerator. Its efficiency, the ratio of output and input energies, is greater than 1 because the ambient energy is […]Read More Can the Efficiency Be Greater Than One?
Subtitle: Dimensional Analysis again. Our photovoltaic generator has about 5 kW rated ‘peak’ power – 18 panels with 265W each. Peak output power is obtained under so-called standard testing condition – 1 kWp (kilo Watt peak) is equivalent to: a panel temperature of 25°C (as efficiency depends on temperature) an incident angle of sunlight relative to […]Read More On Photovoltaic Generators and Scattering Cross Sections
After I presented details for selected days, I am going to review overall performance in the first year. From June 2015 to May 2016 … … we needed 6.600 kWh of electrical energy in total. The heat pump consumed about 3.600 kWh of that … … in order to ‘pump it up to’ 16.800 kWh […]Read More First Year of Rooftop Solar Power and Heat Pump: Re-Visiting Economics
I am sure it protects us not only from lightning but also from alien attacks and EMP guns … So I wrote about our lightning protection, installed together with our photovoltaic generator. Now our PV generator is operational for 11 months and we have encountered one alien attack, albeit by beneficial aliens. The Sunny Baseline […]Read More Alien Energy
I have noticed the impact of traversing clouds on solar power output: Immediately after a cloud has passed, power surges to a record value. This can be attributed to the focusing effect of the surrounding clouds and/or cooling of the panels. Comparing data for cloudless days in May and June, I noticed a degradation of […]Read More The Impact of Ambient Temperature on the Output Power of Solar Panels
July 2015 was the hottest July ever since meteorological data had been recorded in Austria (since 248 years). We had more than 38°C ambient air temperature at some days; so finally a chance to stress-test our heat pump system’s cooling option. Heating versus cooling mode In space heating ‘winter’ mode, the heat pump extracts heat […]Read More Having Survived the Hottest July Ever (Thanks, Natural Cooling!)