you could also do air source heatpump. If your on the coast, and it doesn't get below freezing much, the air source heatpump might serve you well.

This depends on your electric rate though. Expensive electric changes things. What is your electric rate per KW hour total?

Good question. I'll have to look it up.

I just looked it up its 9.3 cents per Kwh.

are you sure thats your total rate? The best way to find the total rate is divide the dollar amount of your last bill by the kw hours used. The rate of 9.3 cents seems unusually cheap.

Have you considered where all those ducts are going to go? For the best efficiency, they should be inside the house envelope. Forced air heat is really nasty when compared to a nice hydronic system. 25 years is not that old for a good oil-fired boiler. My parents' is about twice that age in a much colder region, though they are on their second burner. Efficiency is not that great though so maybe that is what is driving the change. Is there anything wrong with the boiler?

What are you doing for AC now? If it were me in your shoes, I would consider keeping the hydronic and installing heat pump mini-splits.

Yes the oil burner is on its last leg. We will be doing a big renovation so now is the time to update the HVAC. I currently use 2 in the window ac units. The house gets really hot in summer.All i could afford was to but put in window ac in master bedroom and the boys bedroom. I didn't want to expend any $$ knowing I was overhauling HVAC. Will a heat pump work in Northeast?? Our winters can be really cold common for temps in teens. Summers 90's not uncommon.

My last elec bill for August was 2629 KWH @ $.080170

I am shocked at $.09 for a kwh in LI. When I lived there, the rates were 2nd highest in the country. Does that last line mean you are at $.08? That would be really surprising.

At those rates, electric baseboard would be cheaper than oil. A heat pump would be 1/4 the cost of oil at moderate temps so yes, you should have a heat pump.

I grew up on LI and you really don't know what really cold is. Really cold is not getting above zero days on end - that never happens in LI. LI is a pretty temperate area of the NE so generally the NE is not great for heat pumps but LI isn't bad. That being said, a well designed and sized system would be fine. You will use electric strip as backup but that is about the cost of oil so not a big deal. When you really think about it, there are probably just 20 days a year below 20 degrees. That means there are 100 other days of winter (Dec-Mar) that it is warmer than that. So - if you were able to use all HP for 5/6 of the winter, you are doing pretty well. It is more complicated than that but you get the idea.

Geothermal will give you your lowest utility costs but I doubt it is an option. You generally need a little bit of land and you need to have access for heavy machinery. If you have those things, then you just need to call around. LI has an unusual groundwater situation - very sensitive. There might be limits on what you can do by the local governments. Not that geo is at all bad for groundwater but it does use it and LI is a particularly regulatory place.

Forced air vs. hydronic. - we have all been in bad forced air houses. It doesn't mean it is all that bad. But - most everyone prefers hydronic. I grew up in baseboard world and now live in forced air world. With a good system, it just doesn't matter. I've been burned on radiators and dealt with knocking pipes as they warm up. A modern system in either way is better. You do have to find space for ductwork - if you have a basement/crawlspace and an unfinished attic, it isn't a big deal. People will clamor about the ducts not being in conditioned space and it isn't ideal. But compared to using oil for heat, anything is better.

OP, there are not added charges on your electric bill that boost the cost? Just divide $/kWh.