Dawn breaking over the flare and digester 1 as we do the composition testing on the gas intake to the engines

Dawn breaking over the flare and digester 1 as we do the composition testing on the gas intake to the engines

A nice early night last night meant a full eight hours before the alarm this morning which was bliss. Today was a fairly varied day all in all. There was a ground frost this morning which meant that Thorsten and Georg were devoted to trying to muck-spread while the ground was hard enough to hold the tractor and 19 tonne trailer. There hasn’t been a single snowfall this year and few frosts so there have been few opportunities to get the gulle (nutrient-rich digestate end product, effectively liquid manure) out on the fields over the winter which is important for a few reasons. First, spreading the digestate end product provides nitrogen, phosphorus and calcium reducing the need for (and cost of) conventional fertiliser. Second, this process closes the nutrient cycle (which is important for the sustainability of biogas). And finally, the enormous tank where the end product is stored was at least 80% full and once it’s full there’s no way of storing the digestate, and no where to put it!

Inside the digester during agitation. Looks like a Martian (or otherworldly) landscape apparently...?

Inside the digester during agitation. Looks like a Martian (or otherworldly) landscape apparently…?

Up to mid-morning we steadily got on with our testing and routine tasks while service engineers maintained one of the gas engines to ensure optimal efficiency and in preparation for upcoming emissions testing. Following the frosty early start, the day turned into beautiful sunshine in a cloudless sky and the PV installations in this part of the world started gearing up to donate to the grid. Thorsten dropped by around mid-morning to see whether Tim and I wanted to join him for some muck spreading as there’s a spare seat in the big tractor so we split the time and while I finished off that series of tests Tim helped fill the spreader and went about videoing the spreading in action. I got a similar slice of action later on and can understand why Christian enjoys muck-spreading so much. It’s thoroughly relaxing to switch on the radio, key in the range to which extend the spreader arms, set the cruise control on the tractor and give a decent amount of field (about 0.7 Ha) a nice wet brown covering before using the ipad/ ipod linked to the GPS tracker to check the field off of the schedule for the day. Yes, there really is that much technology in these tractors!

During a couple of spreading visits Thorsten told me of the importance of diversifying what is grown to spread the risk for crops (last year was terrible for corn but nearly a record for wheat – I think I’ve got that the right way round – on account of the amount of rain and when it fell). It also turns out that the farm is entirely plough-less which surprised me. Not that it was something I’d ever thought about in depth, I admit. It turns out that ploughing is highly energy intensive, kills large numbers of soil fauna and also oxidises the soil requiring a deeper humus layer. On the farm they tend to grow mustard instead during the off-season to control weeds and then when the frost comes it splits the bulbs and the plants die back returning all of the nutrients to the soil which is then rotavated instead before planting. See, not just biogas that’s being taught out here – to be honest I could write a tome on all of the odds and ends I’ve learned in a week out here (and several more on the now known-unknowns that have come to my attention – like why when you dilute digestate of pH 7-8 with distilled water of pH about 7 does the pH of the solution increase to about 8.2 when the digestate is already about 92% water?).

Back for lunch of baked rice with courgette and fennel and green salad which was delicious and topped off by a nut cake of which I had two pieces. I’ve been starving all day and am now going to blame it on the doughnut I had with breakfast (yes, that’s three pieces of cake by lunch time) that was made with a little bit of milk that didn’t really agree with me. (Nothing wrong with the doughnut, which was very tasty, just a bit wrong with me).

As another week’s worth of silage has now been fed to the fermenter there was some shovelling to do to get the remainder off of the ‘sausage’ of corn in the side of the silo. So, we set to that to work off some of the lunchtime calories before getting stuck into the afternoon’s routine.

Tim is king of the maize pile. Oh, and the white thing next to him is the 'sausage' of corn

Tim is king of the maize pile. Oh, and the white thing next to him is the ‘sausage’ of corn

Around 4pm Thorsten asked whether one of us was free to help him lift some boards for one of his friends. I jumped in the car with the friend and spent the next few hours unloading plasterboard from a forklift truck through an upstairs window into the newly built flat his friend has built on top of his girlfriend’s house. Now, when I say on top, I really mean it – they took the roof off, added a spiral staircase next to the front door and installed an entire other floor on the top of the house with the structural work taking about two weeks. Yes, two weeks! The additional storey is constructed entirely from wood and was largely made offsite and then clicked together in place and, although still work in progress, it looked great with high, vaunted ceilings in the eaves of the roof and loads of light flooding in through windows galore. Even though my fingers were now tingling from hefting pallet full of plaster boards – having not entirely recovered from climbing at the weekend – it was nice to have been able to help out a little bit and also great to see how the community here is close enough to help each other out (Thorsten picked up the pallet of boards from a storage yard with the forklift and drove it through the town to the house because he was asked if he could help while at dinner last night). I asked him about this and he said that the guy we helped was really good at exterior painting and woodwork so he’d just call in the favour if he needed some help in the future; isn’t that the way communities should be?

Back for dinner where I’ve got humous and tofutier (fake meat and vegetable) spread to cover the rye bread with before retiring early for a bit of diary writing and perhaps a little work too. Or maybe just preparation for work; we’ll see how tired I feel after this…


 I got a lie in today! I was up AFTER dawn. Imagine that, 8:10 my alarm went off. To tell the truth the body clock was well awake by then anyway but it felt like a slow start. After gulping down a small bowl of porridge and a coffee we got ready for some exercise and Tim and I rode, while Thorsten ran, to the lake in Obernzenn. We met Christian here and ran a few laps of the lake with him before getting back on the bikes for a further 15km on the bikes around the local area. The tracks and trails were really pleasant, heading up into the forest (and joyfully on a mountain bike back down again) before sweeping around the Zenn valley passed the US training base and back to Obernzenn and eventually back to Esbach. 23km before 11 on a Sunday was a very pleasant start to a day off.

Me Christian and Thorsten just before we headed out again for biking/ running with Tim (the photographer)

Me Christian and Thorsten just before we headed out again for biking/ running with Tim (the photographer)

After a thoroughly restorative hot shower we sat down for lunch of veggie burgers and sauerkraut leftover from yesterday’s lunch which was just as tasty as it had been previously. Today is apparently fish day (which occurs in each month containing an ‘R’) so the family had battered carp caught from a local lake.

Another, fixed roof this time, biogas plant (this one is owned by a collection of farmers)

Another, fixed roof this time, biogas plant (this one is owned by a collection of farmers)

After lunch we got to be tourists for a bit and drove out to Rothenberg, an old walled city that survived the bombing of WWII almost entirely intact. En route we detoured to take in a range of biogas plants that are dotted around the Franconian countryside, the vast majority of which also supply district heating, which is awesome. On the drive a few wind turbines also came into view and with the PV and solar-heating panels provided a panoply (sorry, I just love that word) of renewable technologies that were well integrated with the local population. Talking Tim and me through the different sites, Thorsten mentioned something I hadn’t really thought of about biogas, which is that it doesn’t just breed a closed cycle in environmental terms, but as silage, corn and manure are supplied by local farmers, heat distributed to local residents and digestate then spread on local fields, it promotes a circular economy too. Far less dependence on oil and gas from far away, these sites source from, give back to and benefit the local economy, which for rural populations is incredibly important.

DSC_1506_lrRothenberg was very impressive and really like stepping back in time with brightly painted plaster and wood-fronted houses, cobbled streets and imposing church spires and towers interposing the jaunty vertices of the rooftops. We sat for a coffee, pretzel and schneeball (snowball, sadly probably made with butter) for a quick pick me up after walking around the town and the ramparts discussing everything from energy prices to planning permission – in English before you think my German has improved that much.

Back on the farm we headed for dinner with Suzie’s sister (Steffi) and her boyfriend (Patrick) by Obernzenn lake at a restaurant that apparently does very good salads. As we walked in it was as if the restaurant had been planned as between them the group of four locals knew almost everyone already present. We sat down with one of Suzie’s colleagues, her boyfriend and their dog and tucked in to a good dinner. For me it was salad and chips (before you think that’s a dire choice of food to classify as a good dinner it was awesome, with seeds and nuts galore in the salad), while the food around the table ranged from pizza to prawn pasta and schnitzel with potatoes. And there was good local beer too. In addition to the good food, the conversation at dinner was great with lots of joking around. I also realised that here at least, we and the Germans hold our forks differently. Sounds benign, is benign I suppose, but one of those things that you can’t help but be captivated by once you’ve noticed it. Similarly, the locals thought the way we Brits use our gabels is odd so everyone quickly agreed to disagree and we got on with dinner.

The pretty city of Rothenberg from the tower about the main entrance (so many stairs wasn't great for the legs after this mornings exercise)

The pretty city of Rothenberg from the tower about the main entrance (so many stairs wasn’t great for the legs after this mornings exercise)

Back in the room at 8:45 and I’m shattered. So, while I was going to get on with some work I think it’s going to be an episode of something on the laptop and then early to bed. Oooh and I also got the go ahead to put this online as a blog, so perhaps tomorrow I’ll start posting these notes.

A week into the placement and now we’re starting to get used to the early rising schedule – I’m doing that thing of waking up about five minutes before my alarm goes off. I can’t decide whether this is good or not though. On the one hand it’s nice to be ready for the alarm, rather than have it rip you untimely from a pleasant dream, but on the other it’s five minutes of sleep I’m deprived of and, at the moment particularly, I do like my sleep.

Tim preparing the dry matter tests for the maize silage sampled from different heights of the silage pile

Tim preparing the dry matter tests for the maize silage sampled from different heights of the silage pile

Perhaps in response to mine and Tim’s discussion the day before (no, I’m joking before you get any ideas of sabotage) there was a disruption to the normal routine this morning. Surprised not to see the tractor headlights blaring through the dawn with Thorsten loading the feeders, we walked to the erratic flashlight beams that were emanating from by the side of the fermenter. It seems that the feeder had malfunctioned in the night and the alarm to Thorsten’s phone had brought him out at midnight to try to fix it then. Waiting instead for daylight and a bit of warmth (it’s really pretty chilly here out of the sunshine) it seemed that the screw-feeder had just clogged up with material from the macerator. After raking some of it out and restarting everything seemed to be working again and we went about our morning checks, really noticing the impact the feeder outage had on the fermenter on the amount and composition of gas in the plant and the chemistry of the liquid samples we took.

After breakfast we were given another task. Thorsten’s interest for the batteries it seems is to see whether a solar installation with battery storage would be able to power the pumps on the biogas plant that are running 24/7. To work this out, he has installed electricity counters at several points around the AD site, but has no way of recording them. So, we were given a tour of the monitors (on feeders, gas engines and grid connections) and a schedule to monitor them for. With a bit of spreadsheeting in a couple of days it should be possible to see how the demand for energy varies across the site throughout the day.

Before lunch I got the chance to change the oil and filters on one of the gas engines with Thorsten. Once you know what you’re doing I think it’s pretty straightforward but trying to understand the directions while stood between 300kW and 400kW engines it’s a bit difficult to hear!

Me, refilling the oil in one of the motors after filter and oil change...and at this point not completely covered in oil. Win.

Me, refilling the oil in one of the motors after filter and oil change…and at this point not completely covered in oil. Win.

Lunch today was homemade vegan pizza. A bit of a shock to the system for vegetarian Tim but he said he enjoyed it and it really hit the spot for me. This was also accompanied by another really good soup. Honestly, I could well come back the size of a house! For lunch we were also joined by the electrician who is reprogramming the gas engine control system who was telling us about his friend who had a vegetarian wedding last year. I asked if he knew if the wife had a sister and everyone laughed. I don’t understand why – I was deathly serious!

This afternoon we repeated the analysis but also took samples to be sent to an external lab so that we could compare our results with theirs…this could be interesting when the results come back next week. We spent the afternoon finishing off jobs that had accrued through the week and with me holding a ladder for Christian as he painted the support posts for the engine chimney stacks. My German is picking up a bit now with things from school starting to reawaken and I understood the majority of our conversation, which largely involved him joking with me that if I didn’t hold the ladder properly then everything would be bad and he’d be in the local hospital saying “well ****”. No pressure then as he’s at the top of a six-metre ladder resting against a flue pipe in the wind!

Just before dinner I borrowed some glue in an attempt to try to fix the hangers that broke when we returned in the evening to find my clothes rail had fallen over. In the workshop we found Thorsten rigging up a switching system to overcome the melting of the switch in all his 3-phase switching gear. As we walked back to the annex we’re staying in Tim remarked he really liked the view on the farm that everyone just has a go at fixing the problems they face.

Over dinner while speaking to Christa and learning more and more German we found out Saturday is just another day on the farm, which to tell the truth is pretty much what we’d expected. Sunday is apparently a day off (during which Thorsten and Georg only do their morning duties…that’s a day off?) and we’ll maybe be heading to an old walled city that everyone agreed was very nice.

With dinner finished I’ve just caught up on three days of this dear diary and realised I have a fair amount of corrections to start getting on with soon. Still, there’s always a couple of long train journeys too look forward to getting teeth into them in.

You get very pretty sunsets out here that nicely silhouette big bits of farm machinery like tractors...it's been a great week so far, let's hope it continues!

You get very pretty sunsets out here that nicely silhouette big bits of farm machinery like tractors…it’s been a great week so far, let’s hope it continues!

Tim disappearing into the underground viewing section for digester 4 in the dawn light (of lack of)

Tim disappearing into the underground viewing section for digester 4 in the dawn light (of lack of)

With Thorsten away for the day Tim and I were determined to get on with the work we’d been set as well as carrying out the normal testing duties. We finished the snoop testing finding a fairly large leak near one of the portholes to the first underground tank confirming the suspicions of our host.

I'd say that's pretty cheap for a pack of tasty looking veggie wieners. Specially since they even say on the packet that they're glücklich

I’d say that’s pretty cheap for a pack of tasty looking veggie wieners. Specially since they even say on the packet that they’re glücklich

Aside from that the day passed fairly uneventfully save for a pleasant conversation with Georg, Christa and Suzie at lunch which consisted of cauliflower in egg and breadcrumbs with potatoes which I found pretty great.

After dinner that evening we went shopping and had a good chuckle at some of the translations/ transliterations of things. Following a conversation on the first night about humous I bought some so that the Sturm’s could try it and we also visited the beer aisle picking up two recommendations from Thorsten of local beers – a full lager and a double bock.

Back at the farm Tim and I watched a couple of episodes of It’s only Sunny in Philadelphia and come half nine my eyes were closing. Slow news day today…


Meet Thorsten 6:30 and he shows us around the AD plant and takes us through the process. The first thing to do every day is visually check all of the digesters for the level, whether they’ve a foam capping and that the pumps aren’t flooded before checking there is a temperature difference across the activated charcoal H2S filter, which indicates it’s operating. Once these checks are complete, then it is breakfast. Today with all of the explanations, I think we were a little late (around 8).

After breakfast the first job was with Christian, who is the only non-family member that works on the farm full-time. We have to peel the covering for the silage back which involves lugging some pretty heavy sand bags across a pretty slippery tarpaulin on or near the edge of a 15-20ft pile of shifting silage. It’s not as bad as I first thought though, even if carrying the sandbags up to the middle of the pile is a bugger as they just drag you back down towards the side. While I’m on top of the pile Tim gets stuck in with the shovel moving a hefty amount of silage that’s fallen down the crack next to the corn which is bagged in a sausage (Thorsten’s description, not mine). Christian and I first re-secure the covering and then move on to rolling up the netting. Christian seems a good character and despite both only being able to understand a little of what is said we manage to coordinate the nets and he shows me the three different kinds of poop on site, including the freshly delivered chicken. Surprisingly they don’t smell too badly. Honest!

Yep. That is a lotta...

Yep. That is a lotta…

After this I grab a shovel to help Tim finish moving the silage and then after a good amount of shovelling, making us feel like we’ve earned it, it’s lunch. Mittagsessen for the veggies is spaghetti with spinach, onion and olive oil, which I thought was pretty damn tasty especially with a walnut cake for dessert.

After lunch we start on the measurements in the laboratory that Thorsten has built, but a representative from the gas analyser company arrives and we join while he shows how it works, and we get to play too.

The fermenter...it's pretty big!

The fermenter…it’s pretty big!

Then we’re let loose to do the analysis (temperature, gas analysis, solid analysis, FOS and TAC) for the fermenter and the first two digesters/ storage tanks (nachgaerer). This takes the remainder of afternoon but we finish it with some time to spare before dinner so a necessary shower is taken before we sit down with the family again.

For dinner we have the choice of more spaghetti or rye bread with cheese/ jam/ meat which isn’t much of a contest for me really. I mean, the rye bread here is pretty special but who wouldn’t want spinach. Oh, spinach spinach spinach. Oh, and the pasta was with salad too – wouldn’t want you thinking I was deprived of my greens while over here.

After dinner I managed to catch up on a few emails to maintain touch with the homeland but it didn’t take long for the effects of the long day to set in and soon I was curled up on my air bed which is surprisingly comfortable. What is about Germany, why is everything better here?