Swiss Engineer Speaks About Green Energy Community

The Oxford County (Ontario) Federation of Agriculture recently hosted Thomas Boehni, an energy engineer from Switzerland to discuss rural green energy communities. Mr. Boehni, a mechanical engineer by training, runs Boehni Energy and the Environment based in Frauenfeld, Switzerland. At a workshop in Woodstock, Ontario on November 18, 2008 Boehni outlined his work with the village of Hohentannen. This village of 604 inhabitants is pushing to a goal of 50% locally-sourced renewable energy by 2012. The focus is on electricity, heat, and vehicle fuels.

The region around Hohentannen has a population of 250,000 people, and spends roughly $600 million/year on oil and natural gas source from other jurisdictions. By shifting to locally sourced energy sources (even if they cost a little more) significant economic benefits can be captured for the local community, and spending is kept in the local area.

Figure 1. Solar photovoltaic installation on residence Hohentannen

One area Boehni focused on in his presentation is the installation of solar photovoltaic (PV) units in conjunction with heat pumps as a key opportunity that is being widely implemented by farmers and villagers. He focused on optimizing energy capacity from a small footprint. The following conversions outline different approaches to capturing energy from 1 m², according to Boehni:

1 m² solar panel (PV) = 140 kWh electrical/year
1 m² PV with heat pump = 560 kWh heat = 50L oil
1 m² solar thermal heat = 380 kWh heat/year
1 m² corn silage = 1.5 kWh electrical (via biogas)
1 m² grain corn fed to animals = 0.1 kWh energy
(in meat)
1 m² potato = 3.3 kWh energy (as food)
1 m² wood residue (after lumber) =1 kWh heat

In terms of transportation, the Swiss are more apt to drive small vehicles and have more diesel vehicles available in the marketplace. As a result, the use of Straight Vegetable Oil (SVO) is becoming common, blending with diesel at up to 50% during summer months. Note that this is not biodiesel, rather pure oil. SVO is purchased directly from the farmer at a fuel pump on the farm. In terms of using land for fuel, Boehni pointed out that a conventional North American pick-up truck gets about 1 km from the yield from a square meter of canola field, a small economical car gets about 5 km/square meter of canola field, and an electric bike gets about 5000 km with a square meter of solar panel.

Switzerland has an electricity price regime that favours solar panels mounted onto existing roofs, offering about 70¢/kWh, compared to ground-mounted solar panels which get about 50¢/kWh (comparable to the 54 to 80¢/kWh offered for roof mounted solar PV (depending on size) or 44 ¢/kWh for ground mounted solar (>10 kW) in Ontario under the Feed-in Tariff (FIT) Program). But rapid uptake in their electricity system means that some projects don't get the high price. Despite this, people are installing a variety of systems even in the absence of incentives or grants. The motivation to support local industries (one PV manufacturer is located a few kilometers away in Germany) or local sources of fuel (local biomass for use in a district heating system) act as additional motivators for local participants.

Figure 2. Energy efficiency retrofits at local castle in Hohentannen

It is important that we weigh the economic, environmental and social implications of the energy approaches that we advocate. In most circumstances energy efficiency is the first and easiest step that any farming or food processing operation should pursue. In addition to federal and provincial grants being offered for audits or retrofits, usually the payback on energy efficiency steps merit the attention of facility or farm operators. And as technology and societal values shift (for example, the planned phase-out of coal-fired power in Ontario), old assumptions about certain technologies being non-viable or not being relevant for our stakeholders might change. Looking to other jurisdictions can be helpful to motivate and excite us as we move forward here in Canada.

Thomas Boehni can be contacted at boehni@euu.ch

Jake DeBruyn can be contacted at jake.debruyn@ontario.ca

For more information on energy conservation and generation visit OMAFRA's Green energy opportunities on the farm website.