A Year in a Net Zero Energy House

This is my blog focusing on our net zero energy house in Woodstock, NY.

Sunday, January 23, 2011

EV Makers: Here my tiny voice

I am proud to say I have not owned a car since 1989 (and technically I think my parents owned that one). Yes, I have the benefit of living in Manhattan for the past 17 years and have had a walking commute for most of that. However, we do often travel outside the city esp. now with our upstate place. Zipcar and rentals have filled that need. However, they are either convenient and overpriced (Zipcar, Manhattan rentals) or inconvenient and cost effective (suburban rentals). In addition, fossil fuels are not everlasting and pollute. I have spare solar energy and I want an electric car.

Car industry (traditional and upstarts) I'd like to list my EV wants so that at least some of this trickles into gen 2 (the first I'll consider buying):

- 150 miles of range on a full charge (my infrequent but typical trips are 100 miles)
- 50% recharge time in 5 mins; 80% recharge time in 15 mins; and 100% in 30 mins
- Swappable batteries and a network of swap and charge stations (at least on major highways)
- Four door hatchback in roughly cross-over size (I don't really care that much about looks...with technology its always function over form)
- Solar panels on the roof and wherever else you can put them for battery refill; I've also heard of small wind generators that might apply...look into that
- Home charging stations that don't cost over $1,000 including installation and are based on a standard so it outlives the life of the car
- Under $30k all in

That's about it. We're not that far off right now. Get on it.

Sunday, January 16, 2011

Net Zero for 2010 by 73kwh

We made it. We were net positive on our energy use for 2010 by a tiny 73kwh. That's 1.25% (73/5799 kwh used). I guess my engineering work on sizing the solar relative to the geo and general usage was pretty accurate. But maybe it wasn't.

The tweak I made back in Nov raising the geo output temp for the radiant from ~95 degrees to ~105 degrees has initiated big savings. Last winter, we had days when it was cold where the geo ran almost the whole day (both in residence and away). It wasn't because it was struggling to keep up as much as the temp of the water feeding the radiant wasn't high enough to warm the house to the target temp. Thus, the geo kept running as the thermostats were never satisfied. The 95 degrees in the floor was not making our main zone 70 when it was under 20 degrees outside (and wasn't keeping up with 53 when it was below 10 degrees when we were away).

Raising the output temp by 10 degrees raises runtime energy use but only about 10-20% from what I can see. However, its had a dramatic effect on total runtime. The geo can now hit the interior temp even when its below zero (as it was a few days ago) and doesn't run nearly as much. Early signs point to about a 40% energy savings during this Jan compared to last. Projecting that out over the year we'll have upwards of 600-800kwh to spare this year. Looks like just the right amount to power an electric car ;)