He is called a pragmatic doer, knowing his physics and engineering, devoid of ideology. This is how Josef Jenni is introduced in the preface to his document called How can we achieve the energy transition (Wie erreichen wir die Energiewende). It’s a manifesto and a technical overview – by the pioneer whose company had built…
Tag: Renewable Energy
The Heat Source Paradox
It is not a paradox – it is a straight-forward relation between a heat pump system’s key data: The lower a heat pump’s performance factor is, the smaller the source can be built. I would not write this post, hadn’t I found a version of this statement with a positive twist used in an advert!…
Heat Transport: What I Wrote So Far.
Don’t worry, The Subversive Elkement will publish the usual silly summer posting soon! Now am just tying up loose ends. In the next months I will keep writing about heat transport: Detailed simulations versus maverick’s rules of thumb, numerical solutions versus insights from the few things you can solve analytically, and applications to our heat…
On Photovoltaic Generators and Scattering Cross Sections
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…
Half a Year of Solar Power and Smart Metering
Our PV generator and new metering setup is now operational for half a year; this is my next wall of figures. For the first time I am combining data from all our loggers (PV inverter, smart meter for consumption, and heat pump system’s monitoring), and I give a summary on our scrutinizing the building’s electrical…
The Impact of Ambient Temperature on the Output Power of Solar Panels
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…
Economics of the Solar Air Collector
In the previous post I gave an overview of our recently compiled data for the heat pump system. The figure below, showing the seasonal performance factor and daily energy balances, gave rise to an interesting question: In February the solar collector was off for research purposes, and the performance factor was just a bit lower…
Solar Power: Some Data for the First Month.
On May 4, 2015, we started up our photovoltaic generator. Here are some numbers and plots for the first month – and what I plan to do next. Our generator has a rated power of 4,77 kWp (kilowatt peak), one module has 265 Wp. The generator would deliver 4,77 kW of electrical power under so-called…
Two Weeks After Lift-Off
After a little delay our photovoltaic generator went online – we had been waiting for the delivery of this sophisticated addition to our office decoration: People on G+ had very cool suggestions, such as a rotating alien-fighting device throwing darts. Closest to the truth were: fuse box and fire alarm. The box containing two knobs…
We Have Come a Long Way: Rooftop Solar Power Now!
We had considered it already a few years ago – when we decided to live and work in the middle of a dusty and noisy construction site for a few months: The upper part of the roof is inclined by 30° – which is the optimum angle for photovoltaic panels – whereas the windows in…
The Ice Storage Challenge
The more we enjoyed our spring-like winter, the more we were worried if we will ever see much ice in our underground water tank this heating season. So we did what I had announced – we switched off the solar collector completely: Since February 1st our heat pump has been extracting heat energy from the tank…
“An Unprecedented Test for Europe’s Electricity System”
And we will not be able to contribute – by a hair. We have just ordered our photovoltaic generator, and installation is planned for April. It is the (partial) Solar Eclipse on March 20 that made Europe’s Transmission System Operators (TSOs) release an announcement: Under a clear morning sky on 20 March 2015, some 35000…
Cistern-Based Heat Pump – Research Done in 1993
One of the most recent search terms on this blog was: ‘cistern for water source heat pump’. I wanted to double-check and searched for this phrase myself. This was the first Google Search result: Cistern-Based Water-Source Heat Pump System Design … a research paper that had been available for download at the website of Iowa…
A 1970s Pioneer in Self-Sufficient Living
Living in southern France, Jean Pain developed a self-sustaining ecosystem in the 1970s that supplied his home with 100% of the energy needed. He built a 50 tons compost mound from chipped wood – brushwood that had to be cleaned out to lower the risk of forest fires. Heat exchanger pipes were buried in the heap while it was built….
All Kinds of Turbines
I got an interesting question, related to the heat-from-the-tunnel project: Has anyone considered the fact that the water can be used to first drive turbines and then distributed to supply the input source for the heat pumps? I am a water turbine fan, and every time I spot a small hydro power plant on a…
Pumped Heat from the Tunnel
The idea to use a reservoir of water as a heat pump’s heat source is not new. But now and then somebody dares to do it again in a more spectacular way. Provided governmental agencies give you permit, lakes or underground aquifers could be used. Today a (German) press release about a European research project called Sinfonia…
Big Data, Big Plastic Worms, and How to Utilize Your Cellar
Our heat pump system will soon commence its third heating season. The amount of measurement data collected so far has exceeded the capabilities of the software I had once developed; so I crafted a new application based on a real database server. Now you know why I was not very active on social media recently. I have an excuse…
Lost in Translation – an Overdue Update
In this post I try something new: I will keep it short. This is actually an update long overdue. Months ago I have written a post on how to control the four elements that is how to harvest energy from ambient air, solar radiation, the freezing of water, and ground here. A loyal reader told…
Trading in IT Security for Heat Pumps? Seriously?
Astute analysts of science, technology and the world at large noticed that my resume reads like a character from The Big Bang Theory. After all, an important tag used with this blog is cliché, and I am dead serious about theory and practice of combining literally anything. [Edit in 2016: At the time of writing this post,…
elkemental Force 