EV Monitoring

We've added power-usage monitoring to the EV. Tom hooked up a watt-hour meter (the type the power utility uses to measure your electricity usage) to the EV's dedicated power line. By using this meter, it will be possible to tell just how much we're spending to "fuel" the EV. We're going to put the figures up here for you to see.

Date	Meter Reading	Odometer Miles	Miles Traveled	Miles Per kWh This Period	Cost Per Mile This Period	Miles Per kWh Overall	Cost Per Mile Overall
2/21/98	0	863	---	---	---	---	---
3/3/98	59	1055	192	3.25	$.0215	3.25	$.0215
3/20/98	133	1233	178	2.41	$.0291	2.78	$.0252
6/1/98	373	2043	810	3.38	$.0207	3.16	$.0221
7/1/98	455	2399	356	4.34	$.0161	3.38	$.0207
8/1/98	560	2878	479	4.56	$.0153	3.60	$.0195
9/1/98	636	3213	335	4.41	$.0159	3.69	$.0189
10/1/98	695	3498	285	4.83	$.0145	3.79	$.0185
11/1/98	809	3928	430	3.77	$.0186	3.79	$.0185
12/1/98	935	4307	379	3.01	$.0233	3.68	$.0190
1/1/99	1068	4663	356	2.68	$.0262	3.56	$.0197
2/1/99	1228	4986	323	2.02	$.0347	3.36	$.0208
3/1/99	1365	5355	369	2.69	$.0260	3.29	$.0213
4/1/99	1502	5703	348	2.54	$.0276	3.22	$.0217
5/1/99	1627	5995	292	2.34	$.0300	3.15	$.0222
6/1/99	1730	6434	439	4.26	$.0164	3.22	$.0217
7/1/99	1873	7165	731	5.11	$.0137	3.36	$.0208
8/1/99	1954	7548	383	4.73	$.0148	3.42	$.0205
9/1/99	2086	8155	607	4.60	$.0152	3.50	$.0200
10/1/99	2163	8424	269	3.49	$.0200	3.50	$.0200
11/1/99	2263	8697	273	2.73	$.0256	3.46	$.0202
12/1/99	2373	9008	311	2.83	$.0248	3.43	$.0204
1/1/00	2526	9339	331	2.16	$.0324	3.36	$.0209
2/1/00	2652	9494	155	1.23	$.0569	3.25	$.0215
3/1/00	2813	9825	331	2.06	$.0340	3.19	$.0220
4/1/00	2918	10115	290	2.76	$.0253	3.17	$.0221
5/1/00	3020	10353	238	2.33	$.0300	3.14	$.0223
6/1/00	3074	10445	92	???	???	???	???
7/1/00	3155	10786	341	4.21	$.0166	3.15	$.0223
8/1/00	3232	11137	351	4.56	$.0154	3.18	$.0220
9/1/00	3273	11331	194	4.73	$.0148	3.20	$.0219
10/1/00	3335	11552	221	3.56	$.0196	3.21	$.0218
12/1/00	3513	11893	341	1.92	$.0365	3.14	$.0223
1/1/01	3608	12048	155	1.63	$.0429	3.10	$.0226
2/1/01	3699	12240	192	2.11	$.0332	3.08	$.0228
3/1/01	3774	12355	115	1.53	$.0457	3.05	$.0230
4/1/01	3872	12489	134	1.37	$.0512	3.00	$.0233

Update 4/1/01 -- Starting this month, the car will be garaged for its conversion to NiCD batteries. See our report on the conversion process for more details.

Update 6/1/00 -- OOPS! This month, we don't have useful energy usage information due to the fact that we have been charging the new electric pickup (see our E-10 Restoration page) using the Force's outlet! This is now corrected, as the E-10 now has its own outlet, on a separate meter. Next month we'll have a return to meaningful numbers, since we can't guess how much the truck actually put on the meter.

Update 1/1/00 -- A high energy-usage month! Our mileage was down quite a bit because we have been using the electric heat extensively. Another factor in this month's usage is the fact that we parked the car outside for over a week in very cold temperatures (around 0 degrees F) while I used the garage to do a large woodworking project. This caused the car to use its thermal management system to warm the batteries, which uses a bit more electricity.

Update 12/22/99 -- As of today, we have owned our Force for two years. It has become our primary transportation, and has proven itself to be a very reliable vehicle, with only two days of down-time due to a charger failure in late 1998 (and it was only down those two days because it was a weekend and the replacement charger, shipped by Federal Express on a Friday, arrived on Monday).

Update 7/1/99 -- With this month's trip to Amherst, Wisconsin (303 miles round trip), we have the highest number of miles we've ever travelled in a month (731), and just coincidentally, our highest efficiency ever, at just over 5 miles per kWh! See our Trip to Amherst page for details on the trip.

Update 6/1/99 -- Lots of news on this report. First, this reading gets a full year of regular energy usage under our belts and lets us see just how the car performs over an entire year. Based on this information, we can see that our photovoltaic system must generate approximately 1400kWh over a typical year (or 3.7kWh per day) to offset the car's usage. It should be able to do this. Also, note the drop in efficiency recorded on 5/1/99 (2.3 miles per kWh) -- This was an indicator that something was wrong -- The miles per kWh usually goes up as the weather warms up. It turns out that the car's tires were low on air pressure, causing it to work harder and use more energy to get where we were going. Moral: check your tire inflation regularly (even on internal combustion cars)! I fixed the inflation problem and you can see the jump in miles per kWh on this month's reading. As of this reading, the car is getting its energy from the sun, so the cost per mile figures from here on are strictly informational only.

Over the long-term, an EV winds up costing about the same amount to run as an internal-combusiton vehicle. The benefits are lower pollution (pollution occurs only at the power plant, where it is easily controlled) and the fact that the EV uses energy more efficiently than an internal-combustion engine (ICE):

EV uses 3409.5 / 3.25 = 1049 BTUs Per Mile (using 3/3/98 Mile/kWh figure)
ICE uses 125,000 / 35 = 3571 BTUs Per Mile, assuming 35 MPG

For our van, which gets 23 MPG, the calculation is:
125,000 / 23 = 5434.7 BTUs Per Mile
This makes the EV 5.18 times as efficient!

As time goes on and we gather more details on various aspects of our EV, we'll put more technical information here.