Welcome to the year 2027. The year where the net metering policy in the Netherlands stopped. This post is about owning a home battery system in 2027 onwards and the benefit it has financially, based on minute precise real-world usage- and solar data collected in 2024. In my previous blogpost about the Sessy Home Battery Experience, owning a home battery + dynamic contract resulted in €161.42 more annual profit than without a home battery and a fixed price contract....

Back in 2020 I wrote a post about Simulating a Tesla Powerwall. Much has changed since then. Electricity prices went up and down(!) Energy providers started offering contracts with dynamic hourly prices based on the hourly market value of electricity. The deadline for net metering has been postponed in the Netherlands and now has a final deadline, January 1st, 2027. And related to my setup at home, I managed to change the timing of heating the hot-water storage tank through a hidden management interface....

In a previous blog post I wrote about collecting server statistics with Collectd, passing them to InfluxDB and graphing them with Grafana. Using “Retention Policies” (RPs) and “Continuous Queries” (CQs) metrics could be downsampled to reduce storage usage. This blog post shows how to do the same with InfluxDB v2. InfluxDB v2 At the end of 2020 InfluxDB v2 was released. Moving to InfluxDB v2 with the setup I had (Collectd input, downsampling) came with some challenges:...

It’s a little over a year ago that I got solar panels installed on my roof. Not a Tesla Solar Roof, but the most efficient solar panels available last year. From SunPower. The SPR-X21-350-BLK. Together with a SolarEdge SE5K converter its producing 5300 Watt during peak hours. I’m interested if a Tesla Powerwall is worth it financially. Will it pay back the investment in a reasonable amount of time? In the Netherlands there is still a net metering policy until 2023, which means that you can administratively subtract the electricity you have delivered to, from what you have used from the electricity network....

In the Mendix Cloud we run thousands of Mendix apps on Cloud Foundry on AWS. Mendix Runtime Engines that currently run in 2, 4, 8 or 16 GB memory containers. Mendix developers have the possibility to start, stop, scale and upload new versions of their app themselves via our Developer Portal. This results in the fact that we must have diego-cell instances with at least 16 GB memory available at all times so that a Mendix developer can start their 16 GB memory Runtime Engine....

Almost 10 years ago I started developing a web frontend for collectd, Collectd Graph Panel (CGP). A PHP frontend that displays graphs in PNG format using rrdtool and the RRD files created by collectd. A lot has happened since then. Because of the IoT hype time series databases like Graphite, InfluxDB and TimescaleDB became more popular. Also visualization tools gained more traction, of which Grafana is the most popular one....

A while ago I was researching the possibilities to measure the power consumption of some devices in my house via Wifi. I came across the Broadlink SP3S Smart Plug. It met my requirements: relatively cheap, power measurement and Wifi. It comes with an IOS and Android App. There a big chance the app is not directly connecting to the SP3S, but to “the Cloud” where the SP3S sends its data to....

At home my FTTH Internet connection is provided by XS4ALL. They provide a FRITZ!Box router to connect to the Internet. Instead of using the FRITZ!Box I’ve always used my own Debian GNU/Linux machine to route traffic to the internet. The XS4ALL uplink has 2 VLANs: VLAN4: TV (bridged, RFC1483) VLAN6: PPPoE IPv4 + IPv6 internet connection My XS4ALL uplink is connected to a managed switch. My Motorola 1963 TV Receiver is directly connected to an untagged VLAN4 port on my switch....

In a marathon program from Christmas to New Year’s eve NPO Radio 2 broadcasts the so called “Top 2000“. A list of the 2000 most popular songs of all time. Because I’m not able to listen all 2000 songs in one go, I like to have them on a USB drive in MP3 format, so that I’m able to listen for example in my car. The shell script below downloads the full “Top 2000” of 2023 in MP3 format from the official website....

Debian Stretch was released last month, so it is time to upgrade my laptop. I’m an i3 window manager user. Previously my procedure was to backup /home, reinstall using the network installer (I don’t like apt-get dist-upgrade, I like to start clean) and tick the “Debian Desktop Environment … GNOME” checkbox and after the installer was done, install i3 and the rest of my tools. While I use some of the tools from Gnome, like gnome-terminal, network manager, nautilus and Eye of Gnome, I do not really need the complete Gnome desktop environment and 100s of software packages that come with it....