Category Archives: Uncategorized

Eden Hall Pizza Oven

The Eden Hall pizza oven is a great way to be able to cook pizzas with a great taste.  However, this form of cooking releases large amounts of carbon dioxide (about 5.75 kg CO2 per pizza!).   Meanwhile, an electric ovens at the EBC could emit as low as about 1.65 kg of CO2 per pizza on average largely due to the grid usage of coal and natural gas ovens can emit as low as approximately 0.4 kg of CO2 per pizza!  While natural gas is the best option now for a pizza oven, as Eden Hall’s energy system and the state of Pennsylvania’s energy system evolve and become more renewable, electric ovens will become far better and hopefully emit no CO2 at all!

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The use of the lovely wood-fired oven near the amphitheater should be for every once in a while and special occasions.  Besides, not being able to have it every day makes it taste so much better when that special occasion finally arrives!

Wind Energy Innovations for Eden Hall

Chatham’s Eden Hall campus has taken great strides to be completely sustainable, but there is still more that the institution can do to reach the goal of truly being 100% renewable. As seen in figures 1-3  in Leah Whitacre’s post, we still have deficits that require us to pull from the fossil fuel-powered grid.

Eden Hall has historically invested in solar as its main renewable energy source because it is much more cost-efficient than wind, however in an area that has limited solar potential, particularly in the wintertime, it presents issues of limited power being produced and thus Chatham relies on natural gas to power our campus.  

We can break this reliance on fossil fuels through the further integration of wind energy into our energy production.

Recently we have invested in a Windstax vertical turbine, which you can learn more about in this video by Chatham! The system is quiet, easy to use, and can produce up to 4000w (continuous) and 11,336 – 18,330 kWh per year for a medium-sized system. 

I would like to propose that Eden Hall invests in building a small wind farm to power our campus and obtain the ability to be 100% renewable. This would assist in powering our campus during times when there is a lack of sun available, and we would be able to use net metering to sell back to the grid when there is excess energy available. Considering Eden Hall’s region of Pennsylvania doesn’t have the most ideal wind potential, a partnership with solar would be needed. However our campus does benefit from the fact that it is on the highest peak in Allegheny County, and so there is greater wind potential than most of the region. (WindExchange, 2020) 

 The most ideal way to do this would be through investing in more of the Windstax vertical turbine. 

It’s local, it provides data, it acts as a generator in times of need, and most importantly we already have experience with the system, so it would be easy to integrate 2-6 more systems into our community if the funding was available. Another way of doing this would be to invest in a new system, such as the Vortex bladeless wind generator.

The Vortex is a 2.75-meter tall rotational generator that uses the wind to make a slim cone-like structure swing back and forth to use the aerodynamic effect of vortex shedding to generate electricity through an alternator system. Additionally, it also has no avian mortality due to its bladeless design. (Vortex, 2020) The low maintenance, virtually silent system seems like a perfect fit for any campus, however, it has not yet been available for purchase. The operation is in its final stages of production and seeks partners to make the system more widely available. At its current stage it can produce up to 100w per unit, but Vortex plans to make the system low cost and affordable so it may be accessible and suitable for wind farms. (Vortex, 2020) A partnership or investment in Vortex would be a way of showing dedication to diversity and creativity in the many forms of renewable energy and would be a teaching tool to showcase new and non-traditional forms of wind energy. 

Learn more about Vortex by checking out this video and comment your thoughts about these suggestions for Eden Hall below!

“Solar power, wind power, the way forward is to collaborate with nature – it’s the only way we are going to get to the other end of the 21st century.” ~ Bjork

Got Gas?

As many of us know, Pennsylvania is a hot spot for fracking and the use of natural gas as an energy source. In 2019 alone, Pennsylvania’s net electricity generation was composed of natural gas supplying 49%, followed by nuclear at 34% and coal at 14%; Hydroelectric and other renewable energy sources only contributed around 3% to the net electricity generation in the state. While the use of natural gas is often thought of as a better alternative to coal because it produces less CO2, fracking for natural gas produces methane – a greenhouse gas significantly more potent than carbon dioxide. Additionally, the fracking operations are not required to report or manage the chemicals that they use in the fracking process, so many carcinogens and toxic chemicals end up getting leaked into our watersheds. There is no way to hold these companies accountable when health issues start to increase because the chemicals cannot legally be tracked back to their origin.

Here at Eden Hall, our energy usage in 2019 looks quite different from Pennsylvania as a whole, but we still have room to improve. In the newer buildings (the EBC, Cafe Ann, Field Lab, and Orchard Hall), the geothermal system takes care of our heating and cooling needs, so the following data only refers to the energy we produce and consume. However, this discussion does not touch on the amount of energy that the older buildings (the Lodge, Morledge House, etc.) consume from the grid for both heating and electricity needs. Additionally, the data for solar production from Cafe Ann is not included in this discussion largely because there was no corresponding data for how much energy was consumed in that structure (due to its lack of use). Keep in mind that although this structure does produce more energy than it consumes, its maximum solar output for any given week over the course of the past three years is a little over 200 kiloWatt hours. The following figures are measured in thousands of kWh.

For the Esther Barazzone Center in 2019, the amount of solar energy produced never surpassed the amount Eden Hall was charged for by the Duquesne Light Company. The overall trend makes sense seeing as how the deficit increases during the winter months and comes close to breaking even once we reached summer. Also, the original plan was for there to be additional solar panels in order for the EBC to be net-zero. This canopy setup was unable to come to fruition, but it is important to note that the amount of solar production showcased in Figure 1 was not the intended amount.

Figure 1: Energy usage in the Esther Barazzone Center

Figure 2: Energy usage in the Field Lab

Figure 3: Energy usage in Orchard Hall

In Figure 2, it is clear that it is possible to produce more solar energy than we need to pull from the grid. However, we still face the same large deficit once we get to the winter months. In Figure 3, we see that Orchard Hall also produces almost all of its electrical energy needs during the summer month. It should be noted that the data source for this graph had some discrepancies in the solar data, so the first half of the graph is not entirely accurate (the numbers used are most likely too low during April and July). However, the trends that we have seen before continue with the largest difference between energy used from the grid and energy that we produce occurring during the winter. What is important to understand here is that while Eden Hall has incorporated a lot of renewable energy systems and is headed in the right direction, we are still quite reliable on the fossil-fuel-based grid.

Biogas Usage
One potential solution for mitigating our dependency on fossil fuels via the grid is investing in biogas technology. Biogas is often created using animal manure, food waste, and other substances containing organic compounds. A CMU student-led start-up called Ecotone Renewables has created an anaerobic digestion system, the “Seahorse” (see below) with the bulk of the system contained within a 10×20 foot shipping container and a hydroponics greenhouse setup on top of it. This project can process about 385 pounds of food waste per week, and it produces about 50 gallons of fertilizer per week as well as methane gas for energy production. This could be beneficial for use at Eden Hall potentially with the older buildings because they are already set up to use natural gas from the grid that could be replaced with the gas produced from the Seahorse. While this system still includes the use of the highly potent greenhouse gas methane, we could begin the transition of the older buildings by sourcing our gas from food waste rather than fossil fuels. It is unclear if the Eden Hall campus would produce too little or too much food waste per week for this system, and their public resources do not share how much energy this system would generate at max capacity, but this project has the potential to help Eden Hall decrease our dependence on the grid and, by extension, fossil fuels.

Native Wildflowers & Solar Panels!!

Hey everyone! I wanted to give some spotlight to some awesome native flowers that can be incorporated into solar operations. Biosolar, more recent term, describes to co-placement of vegetation & solar operations since vegetation improves the efficiency of solar panels and solar panels provide shading and create micro-climates for cropping & planting. I think it would be beautiful to make our solar spaces more green & better for pollinators as well!

Swamp milkweed (Asclepias incarnata)

Swamp milkweed (Asclepias incarnata), Maine native ...

Not only are these beautiful purple/pink plumes appealing to our eyes, they are also appealing to, not only our bees, but also to those of butterflies, specifically monarchs! They take up water well and would be a great fit for our rain gardens. I have also found that they deal well with low oxygen levels in the soil, making them a more hardy plant.

Appalachian Mountain Mint (Pycnanthemum flexuosum)

PYCNANTHEMUM Flexuosum -Menthe américaine – Big Leaf ...

The dainty white flowers of this more uncommon mountain mint species are both beautiful and important, as they attract all different species of bees and the Gray Hairstreak Butterfly. Named after our Appalachian region, these flowers make a nice aromatic addition to any garden and develop red foliage in the fall.

Wild Bergamot (Mondarda fistulosa)

Wild Bergamot (Monarda fistulosa) for NABA certified ...

This upright, lavender flowers attract both bees, butterflies, and hummingbirds! Not only are they a beautiful aromatic, they can also be used to make earl grey tea. It is a host to the hermit sphinx, orange mint moth, and the raspberry pyrausta as well, all being interesting moths to be observed at the campus Moth Observation Station.


Geothermal Energy for Morledge House!

I propose that Morledge Hall gets switched to geothermal heating and cooling to save money and increase the amount of renewable energy being used at Eden Hall. Currently about $4700 is spent on gas and electric for Morledge Hall now (building used for K-12 education outreach). By switching to a geothermal system, 30-60% on heating and 20-50% on cooling costs can be saved and Eden Hall will be even more reliant on renewables instead of fossil fuels. Geothermal systems are also low maintenance and last a long time with the indoor components lasting about 25 years and more than 50 years for the ground loop. Using a BTU calculator, based on the size of 2,401 ft2, an average ceiling height of 8ft, about 4 people inside the building, and average conditions on sun exposure and climate with poor insulation then Morledge House uses 61,824 BTUs or 5.2 tons. This would mean Morledge House needs a 5-ton geothermal unit. Before the geothermal system is added, the insulation should be improved so heat is not being lost. A contractor will help size the other pieces and parts like the boreholes and depth of locations of the pipes. A procedure called Manual J is completed to determine the heating and cooling loads (capacities) based on the house structure, size, number of doors and windows and the type, insulation, duct leakage, winter and summer conditions and other factors. This will be a more exact evaluation to determine the number of Btus needed. Manual S procedure is used to select the right equipment such as the duct work for the proper air flow, air handlers, electric resistance heat, thermostats. A contractor would also have to determine the size of the borehole and length of pipe. HDPE pipe is relatively inexpensive and geothermal kits are oversized when it comes to the linear feet of ground loop pipe (700 per loop). The pipe should be placed ensuring the pipe is below the frost line about 6-8 feet deep. Based on these facts, Morledge Hall should have about 700 feet of ground pipe per loop (two loops like Orchard Hall totaling 1400 feet) and the depth should be about 7-8 feet below the ground.